Form 1
Concept ofgeography
Meaning of geographyphenomena
(Not present in exams)
Importance ofgeography
(Not present in exams)
The solar system
The concept of a solarsystem
(Note that Pluto is no longer considered a planet)
Order of the planets -
1. Mercury
2. Venus
3. Earth
4. Mars
5. Jupiter
6. Saturn
7. Uranus
8. Neptune
The four inner planets from the sun namely Mercury, Venus, Earth and Mars are referred to as “terrestrial planets” because - They are all relatively small, rocky in composition and clustered together close to the sun and they are visible to the naked eyes, which means they resemble Earth
Examples of celestial bodies - Asteroids, moons, planets and stars Aphelion - The position of the Earth when it is furthest from the Sun Asteroids - Rocky planetary bodies which orbit the sun
Eclipse - Occurs when three heavenly bodies (e.g. planets/stars) are in one line and one of them is a source of light such as when the moon comes between the Sun andEarth
Equinox - Occurs twice a year, when the tilt of the Earth's axis is inclined neither away from nor towards the Sun, the centre of the Sun being in the same plane as the Earth'sequator
Meteorites - Pieces of hard matter such as rocks falling from outer space
The Milky Way - The galaxy which contains our solar system and the planet Earth, it is our galaxy
Tides are highest during an eclipse
The sun is the main source of light, heat and energy for Earth
The lunar eclipseis evidence which proves that the Earth is spherical
TheEarth
The rotation of the Earth causes - Day and night, difference of one hour between two meridians of 15°, the deflation of winds and ocean currents, the daily rising and falling of ocean tides
Earths movements are caused by isostatic adjustmentDay and night are caused by the rotation of the Earth
The Earth shape is a flattened sphere called a geoid or oblate spheroidThe rotation of the Earth causes the deflection of winds and ocean currentsPangea was divided into two parts called Laurasia andGondwana
The four seasons which occur on the earth’s surface are result of the revolution of the earth
Deflection - Due to spinning effect of the earth, water and air currents do not travel in straight lines
Coriolis Effect (Ferrel’s Law) - Is an apparent deflection of moving objects when they are viewed from a rotating reference frame
The Earth has an angle of inclination of 66½ degrees which causes the variation in the length of day andnight
The importance of parallels and meridians
Chronometer - Is a clock which is precise enough to be used as a portable time standard; it can therefore be used to determine longitude by means of celestial navigation
Latitude - Angular distance east or west of the prime meridian, used for north-south measurement
Longitude - Is the geographic coordinate used for east-west measurement
Meridian (Line of Longitude) - Is an imaginary arc on the Earth's surface from the North Pole to the South Pole that connects all locations running along it with a given longitude
Prime Meridian - Is the meridian (line of longitude) at which the longitude is defined to be 0° which runs through Greenwhich UK
Summer Solstice - Occurs exactly when the Earth’s axial tilt is most inclined towards the sun at its maximum of 23° 26’. In the Southern Hemisphere it occurs on December 22, in the Northern Hemisphere it occurs June 22
Great Circle - A circle in the surface whose plane passes through the centre of the globe, used to plot routes for ships and planes across great distances
Horse Latitudes - Sub-tropic latitudes between 30º and 35º in both the North and South Hemispheres Circle of Latitude - An imaginary east-west circle connecting all locations that share the same latitude Tropic of Capricorn (Southern Tropic) - Marks the southerly latitude at which the sun can appear directly
overhead at noon, occurs during the December solstice
Tropic of Cancer (Northern Tropic) - Marks the northerly latitude at which the sun can appear directly overhead at noon, occurs during the June solstice
Winter Solstice - Occurs exactly when the Earth's axial tilt is farthest away from the sun at its maximum of 23° 26'. In the Northern Hemisphere, the Winter Solstice occurs on December 21, in the Southern Hemisphere it occurs June 22
Major features of the earth’ssurface
Continents
(Not present in exams)
Waterbodies
(Not present in exams)
Weather
The concept of weather
Atmosphere - A blanket of air or other gasses which surrounds planets including Earth
Mesosphere - The middle layer of the Earth’s atmosphere
Tropopause - Is the atmospheric boundary between the troposphere and the stratosphere
Troposphere - The lowest portion of the Earth’s atmosphere
Order of layers of the Atmosphere from lowest to highest -
Troposphere - Ends atthetropopause - Lowest
Stratosphere Mesosphere Thermosphere
Exosphere -Highest
Elements of weather
How to calculate Fahrenheit and Celsius -
[°C] = ([°F] − 32) × 5⁄9
[°F] = [°C] × 9⁄5 + 32
Types of rainfall - Convectional rainfall, cyclonic rainfall, orographic rainfall
Convectional Rainfall - Occurs when the atmosphere becomes heated more than its surroundings leading to upward motion, rain falls from convective clouds like cumulonimbus clouds
Cyclonic Rainfall - Occurs who masses of air with different density (moisture and temperature) meet, warmer air rises over cold air which produces precipitation (rain)
Orographic Rainfall - Is caused when masses of air pushed by wind are forced up the side of elevated land formations like mountains
Weatherstations
The suitable area to set up a weather station is on fairly level ground in an open space
Climate
Concept ofclimate
Climate - Is the temperature, humidity, atmospheric pressure, wind, rainfall, and other meteorological elements in a given region over long periods of time
Clouds - Small particles of condensed water at the lower part of the atmosphere
Constant Volume Gas Thermometer - Measures temperature by the variation in volume/pressure of a gas
Desertification - Is the process of forming desert by increased heat on the Earths surface causing evaporation or by the destruction of forests
Dew - Is water in the form of droplets that appears on thin, exposed objects in the morning or evening
Doldrums - It is an area with low pressure in the tropics
Drought - A prolonged lack of moisture in an area as a result of a long period without rainfall
Fog - Is a cloud that is in contact with the ground
Front - The zone separating two air masses
Hail - Is a form of solid precipitation which consists of balls or irregular lumps of ice
Humidity - Is the amount of water vapor in the air
Hygrometers - Are instruments used for measuring relative humidity
Inter-Tropical Convergence Zone (ITCZ) - The zone between the maritime and continental air masses
Land Breezes - Occur at night due to the fact that land temperatures drop faster than water (because of different specific heat values), so it is cooler on the land than water
Macroclimate - Refers to the regional climate of a broad area
Maximum Temperature Thermometer - Used to measure the highest temperature reached in a day
Microclimate - A detailed small scale study of weather elements within a natural environment
Mist - Is a phenomenon of small droplets suspended in air
Polar Front - Where cold air from the Polar Regions meets warmer air from lower latitudes
Relative Humidity - Is the amount of water vapor that exists in a gaseous mixture of air and water vapor
Sea Breezes - During the day the breeze comes from the sea because the land is warmer and air travels from areas of high pressure to areas of low pressure
Sleet - A mixture of snow and rain
Trade Winds - Winds blowing from horse latitudes to the equatorial belts. Found in the tropics in the lower troposphere. Used in the past for trade and conquest by Europeans
Tropical Cyclone - A low pressure center with develops in low altitudes
Tsunami - A strong wave in the ocean caused by an earthquake or by a volcanic eruption
Weather - The state of the atmosphere measured by hot or cold, wet or dry, calm or storm, clear or cloudy Hurricanes and typhoons are tropical cyclones
Salinity of ocean water increases with an increased rate of evaporation of ocean waterWind blows from areas of high pressure to areas of low pressure
Weather andclimate
(Not present in exams)
Impact ofclimate
(Not present in exams)
Mapwork
Concept of amap
Choropleth Map - Is a thematic map in which areas are shaded or patterned in proportion to the measurement of the statistical variable being displayed on the map, such as population density or per- capita income
Atlas - Is a collection of maps; it is typically a map of the Earth or a region of the Earth
Components of amap
Contours - Lines that are drawn on the map joining different places with the same height above sea level
Isobar - Is a line connecting points of equal atmospheric pressure Isobeth - Is a line joining all place with equal depth in the ocean Isohel - Is a line of equal or constant solar radiation
Isohyet - Is a line joining points of equal precipitation on a map
Isoneph - Is a line indicating equal cloud cover
Time Zone - Is a region on Earth, more or less bounded by lines of longitude, that has a uniform, legally mandated standard time, usually referred to as the local time
Quantitative information aboutmaps
Essentials of a map - Key (legend or reference), scale, margin (frame), title, indication of north direction
Ways of showing topographical features on a map - Using contours, hill shading, layer colouring, form lines, hachure, benchmarks, spot height, trigonometrical stations (points)
Techniques of expressing scale of a map - Linear scale, statement (verbal) scale, representative fractional scale (RF scale)
Uses ofmaps
(Not present in study guide)
Humanactivities
Concept of humanactivities
(Not present in exams)
Form 2
Agriculture
Small scale agriculture
Small Scale Agriculture - Growing enough food for a family or small population, with little or no extra food for sale (ex subsistence farming)
Outline the main characteristics of small-scale agriculture - Simple tools are used, areas are small, low production, crops are starch based, poor transport, less use of chemicals to control diseases, family labour is used, local superstitious beliefs dominate among farmers
Effects of farming of on the environment - Erosion, destroys bacteria in the soil, overgrazing, deforestation, chemicals, artificial fertilizers tend to increase soil acidity, monoculture destroys fertility
Types of irrigation - Basin Irrigation, overhead irrigation, trickle irrigation, canal irrigation, tank irrigation, irrigation using lifting devices
Explain the tools or ways of empowering women in social and commercial activities - Giving education, loans, incorporating them into decision making, entrepreneurship training
Farming - Is the process of producing crops and keeping animals
Irrigation - Is the practice of ensuring that plants get enough water through artificial methods like the construction of dams, canals or tubes
Mixed Farming - The process of planting trees and growing crops in the same farm unit
Large scaleagriculture
Large Scale Agriculture - Growing of large amounts of crops to feed the population as well as for sale (ex. cash crops)
Disadvantages of large scale farming in Tanzania - Needs large capital investment to establish and maintain, dependent on crop prices, requires a lot of land, can lead to environmental degradation, contributes to migration to farming areas for employment
Causes of the failure to satisfy food demands in Africa - Poor technology, insufficient capital, climate failures, poor policy and implementation, pests/diseases, low level of education, rural-urban migration
Livestock keeping
Livestock Keeping - The practice of having animals such as goats or cows to provide milk, meat or economic value to an individual or family
The problems of beef cattle production in Tanzania - Insufficient capital, lack of adequate cold storage, transportation system, lack of markets, low quality of beef, diseases and pests, shortage of water and food for cattle, tradition of livestock keeping, ignorance of livestock keepers about proper methods of animal husbandry, no emphasis from government on beef cattle production
Beef cattle production can be improved through the following ways - Improvement of transportation and infrastructure, better education of farmers about animal husbandry, explore viability of new markets for beef cattle products, building of adequate storage facilities
Beef Cattle Production - Is the rearing of cattle for the purpose of producing products like meat or hides Destocking - Reducing the number of animals grazing an area of land compared to the lands capacity Overstocking - Is the act of grazing more animals on a piece of land than the land can handle Pastoralism - Is an economic activity whereby people live by grazing livestock on natural pastures Ranching - A system of keeping animals on a large piece of land
Water management for economicdevelopment
Importance ofwater
Economic importance of water - Encourage industrial development, improved family life, generation of HEP, agricultural development, development of transport, fishing industries, soil formation
Explain the need for and problems with irrigation in North Africa - Needs: Areas are semi-arid with low rainfall preventing crops from growing, nomadic groups there are not able to produce enough food for consumption and sale, population is increasing putting pressure on food supplies Problems: Lack of funds in Kenya, lack of modern technology, few irrigation engineers, nomads do not want to settle
Reasons East Africa has not developed an advanced fishing industry - Lack of capital or financial support, poor technology, ocean topography does not encourage fishing grounds, poor market for fish from East Africa, water pollution, poor means of transport, lack of storage facilities
Fishing Industry - Is an economic activity that deals with the production or harvesting of fish
River basindevelopment
The advantages of exploiting the Rufiji and Kagera river basins - Facilitates irrigation farming to produce food and cash crops, enables finish activities by construction of dams, harness water for hydroelectric power generation, source of clean water, provides employment
The disadvantages of exploiting the Rufiji and Kagera river basins - Environmental degradation or pollution, contribute to the loss of biodiversity, expensive infrastructure like dams and channels
Elaborate on the economic importance of forest resources in the Congo basin - Provides raw materials, provides foreign exchange, source of employment, brings economic diversification, develops transportation and communications in the region, can lead to industrial development
Landreclamation
Land Reclamation - The process of turning unproductive land to a useful state such as reclaiming desert land or creating land by filling the seabed
Steps that were taken in Netherlands to reclaim the land - Building of dams and dykes to retain water from the sea, draining of water using canals and pumps, planting reeds to allow water absorption by plants, burning of reeds to clear the area for cultivation, cultivation of reclaimed land
Aims of land reclamation - To control foods, to get more arable land, obtain land for settlement, improve navigation, get clean water
Sustainable use of waterresources
Benefits of establishing Tennessee Valley Authority in the USA - Increase in water supply for various uses, improvement in navigation, hydroelectric power, controlling flooding, creating employment, development of tourism, increase size of arable land, development of fishing industry
Waterpollution
Eutrophication - Excessive growth of algae in rivers and lakes owing to accumulation in the water of minerals such as nitrates which promote plant growth
Ways of reducing pollutants - Locate industry away from residential areas, recycle waste, efficient engines, efforts by government and other organizations to avoid environmental pollution, stronger policies, use of alternative energy resources, develop other safer activities
Sustainable use of forestresources
Types of forestryresources
(Not present in exams)
Importance of forestryresources
Importance of forests - Protect soil from degradation or erosion, habitat for animals, production of oxygen, providing building material, paper making, maintaining water sources, attract tourism, research studies
Afforestation - Is the planting of seeds or trees to make a forest on land which has not been a forest recently, or which has never been a forest
Agroforestry - Approach of using the interactive benefits from trees and shrubs with crops and livestock Reforestation - Is the reestablishment of a forest after removal, for example from a timber harvest Rejuvenation - The renewed activity of an ecological area such as a river or forest
Important areas of forest products, transport anduse
(Not present in exams)
Problems associated with forestry resourcesharvesting
Problems associated with the exploitation of forests - Poor capital, lack of valuable species of trees in tropical areas, dense tropical forests, poor transport, low technology, rapid population growth, challenges from environmentalists, coniferous trees face challenges from acidic rain in temperate areas
Problems facing the forestry industry in developing countries - Uncontrolled and unplanned cutting of trees, bad cultivation methods and burning of vegetation, wild animals destroy trees as they feed on them, depletion which is caused by higher demand for charcoal and firewood, spread of permanent agriculture, poachers and honey collectors, lack of transport infrastructure, developing countries do not set prices for wood products, many trees in tropical areas have no commercial value
Discuss the problems associated with exploitation of forest resources in developing countries like Malawi - Deforestation, drought, landslides, shortage of rainfall, soil erosion, loss of biodiversity
Sustainablemining
Types of mining
Mineral Ore - Is a type of rock that contains minerals with important elements including metals
(Not present in exams)
Types and distribution of mining regions in theworld
(Not present in exams)
Methods ofmining
Shaft Mining Method - Is the method of excavating a vertical tunnel from the top down, where there is initially no access to the bottom
Open Cast Mining (Open Pit Mining) - Is a method of extracting rock or minerals from the earth by their removal from an open pit
Contribution of mining to the economy ofTanzania
(Not present in exams)
Effects of the mining industry in theenvironment
Describe the effects of mining activities to the environment.- Pollution, soil degradation, land exhaustion, accelerates deforestation, disappearance of valuable plant species, greenhouse effects, spread of malaria due to standing water in mining pits
Factors affecting the exploitation of mineral resources - Availability and size of mineral deposits, quality of deposits, availability of capital to extract minerals, transportation system, availability of labour forces, methods used to exploit resources, market prices for minerals, availability of water supply to cool machinery and for washing minerals, government policy towards mining
Focal studies on oil and naturalgas
(Not present in exams)
Tourism
Concept oftourism
Ecotourism - Integrated approach that involves the carrying out of tourist activities with a minimum of negative impacts on the natural environment
Tourism - Is an economic activity which involves movements of people from their normal working places or homes to other places near or far away, for pleasure or recreation
Factors for the development and growth oftourism
Why East Africa is attractive to tourists - Presence of mountains and volcanoes, beaches and coral reefs, culture, art, historical sites, animals, national parks
Importance oftourism
Negative effects of tourism in East Africa - Environmental degradation, environmental pollution, spread of disease, cultural moral decay, spread of illegal drugs, increased government expenditure
Importance of ecotourism to the local community - Leads to empowerment of local economy, living standard is raised, locals gain respect of environment and its resources, preserve culture, builds relationship between visitors and local community, helps control diseases due to gaining of education, reduces water pollution, provide a market for local products (goods), stimulates development of transport, promotes environmental conservation awareness
Focal studies on the tourism industry
Explain the necessary conditional factors that contributed to the development of tourism industry in Switzerland - Availability of capital, good infrastructure and transport, scenery, good climatic conditions, availability of recreational activities, peace, located near other European nations
Manufacturingindustry
Concept and importance of manufacturingindustries
Manufacturing - Involves processing and changing the raw materials so as to make new products
Types of manufacturing industries
(Not present in exams)
Factors for location ofindustries
Outline the factors for the location of manufacturing industries - Availability of raw materials, markets, labour supply, power and energy resources, capital, transport and communication, good government support/policy, water supply
Factors limiting the development of dairy farming in East Africa - Poor capital, poor market, lack of storage facilities, poor breeds, lack of electricity and transport, poor technology, lack of skilled labour
Pollutants from manufacturingindustry
(Not present in exams)
Focal studies onmanufacturing
Importance of manufacturing industries to the world economy - Provides employment, foreign currency, promote development of technology, diversification of economy, leads to self sufficiency, improvement of economic activities like trade/tourism/agriculture, reduces expenses on imports, encourages improvement of social services, development of transportation and communication
Reasons Japan produces ships - Employs modern and advanced technology, possesses highly skilled employees/technicians, iron/steel industries exist in port towns, large and reliable market for ships, geographical nature of Japan, has little land for cultivation, economically developed
Factors for poor development of manufacturing industries in Tanzania - Poor capital, poor market, lack of skilled labour, lack of transportation, lack of technology and communication, lack of electricity
Reasons for the rapid expansion of industries in South Africa - Availability of capital, advanced technology, good transport and communication, ready market, availability of raw materials, presence of skilled and non-skilled labour
Explain the factors favouring dairy farming in Denmark - Development of science and technology, availability of capital, conducive climate, availability of pastures, skilled labour
Reasons for auto industry in Germany - Skilled technicians, advanced technology, availability of capital, ready market, availability of raw materials, power and energy resources, transport and communications
Sustainable use of power and energyresources
Define power andenergy
(Not present in exams)
Major sources of power & resources
Natural Resources - Naturally occurring substances that are considered valuable to human activities
Renewable Resource - Any natural resource that can be used without depleting its reserves
Hydroelectric Power - Use of water to create power through the use of turbines
Wind - Use of the wind to power turbines and create energy
Solar - Use of solar panels to get electricity from the Sun’s energy
Non-Renewable Resources - Resources whose reserves can be depleted
Petroleum - Oil used in cars, heavy machines or lubricants. Burned for energy and pollutes
Precious Stones - Gold, diamonds and other minerals mines for market or industrial uses
Ways to conserve natural resources - Avoid deforestation, make good laws, enforce environmental laws, modernize technology to avoid effects of mining or industry, protect water sources, education
Activities of man that affect natural resources - Agriculture, overgrazing, mining, cutting of trees for timber
Methods of acquiring or extracting power andenergy
(Not present in exams)
Importance and uses of power and energyresources
Preconditions for establishing hydroelectric power - Presence of a sufficient and constant supply of a large volume of water (i.e. lake or river), steep gradient or slope along the long profile of the river, presence of lakes along the river, availability of space to build dams and reservoirs, enough capital to invest and maintain the plant, presence of skilled technicians, modern technology, market for electricity
Advantages of hydroelectric power - Clean power, does not cause severe destruct of environment, dams help prevent flooding, provides employment, easy to maintain after initial installation, stimulates industrial development, developing nations can use hydroelectric power cheaply
Problems facing power and energyproduction
Problems associated with exploitation of energy resources - Pollution, low capital, low technology, lack of ready market, lack of skilled labour
Advantages and disadvantages of natural gas - Advantages: Efficient, cleaner than oil, easy to transport
Disadvantages: Explodes easily, causes air pollution, exhaustible (non-renewable)
Focal studies on wind and solar power in the USA and HEP and biogas inTanzania
Importance of natural gas to Tanzania - Improving standard of living, reducing cost of power, promotes environmental conservation, provide employment, brings in foreign currency, source of government revenue, stimulate exploitation of other energy resources like petroleum
Transport
Main types of transport
(Not present in exams)
Importance oftransport
(Not present in exams)
Problems facing the transportindustry
(Not present in exams)
2.9.0 Form 1 and 2 questions
Environmental lapse rate experiences temperature decreases by 0.6ºC per 100m
A football match started in Town X, 76ºE at 4:30 pm. What would be the time for a town at Greenwich Mean Time(GMT)?
Step 1: Find the difference in degrees of latitude
76º - 0º = 76º
Step 2: Find the difference in time. Divide the difference of degrees of latitude by 15
15º = 1 hour x = 76º
76
15
x 5 1 hours
15
Step 3: Change the fraction into minutes. Multiply the fraction by 60 since 1 hour is 60 minutes
1 * 60
15
x 4 min
Step 4: Find the difference. Moving west is subtraction, moving east is addition
The difference in time is 5 hours and 4 minutes. Since we must move west to reach the Prime Meridian, you need to subtract time
4:30pm - 5:04 = 11:26 am
If the time at Place X, 45º E is 10:00 am, what will be the time at Place Y, 45ºW?
Step 1: Find the difference in degrees of latitude
Since one place is east and one is west, the numbers are added, this is because they lie on opposite sides of the GMT
E + W
45º + 45º = 90º
Step 2: Find the difference in time. Divide the difference of degrees of latitude by 15
15º = 1 hour x = 90º
90
15
x = 6 hours
Step 3: Change the fraction into minutes In this problem there are no fractions to convert
Step 4: Find the difference, moving west is subtraction, moving east is addition 10:00pm - 6 hours = 4pm
Micheweni is at sea level and has a temperature of 32º C. What is the temperature of Karatu at 1500m above sealevel?
Step 1: Find the difference in altitude
1500m - 0m = 1500m
Step 2: Use temperature lapse rate to calculate temperature
Temperature Lapse Rate: 100m = 0.6º C
x is the difference in altitude from step 1
x = 1500m
Step 3: Multiply the left sides together and right sides together of each equation
Equation 1: x = 1500m
Equation 2: 100m = 0.6º C
Final Equation:
100x = 0.6º C * 1500m
Step 4: Isolate x on the left side of the equation by dividing by 100
100x 0.6º C *1500m
x 0.6º C *1500m
100m
x = 9ºC
Step 5: Take x and subtract from the temperature of Micheweni, you subtract because Karatu has a higheraltitude
32ºC - 9ºC = 23ºC
What is the longitude of Morogoro if its local time is 10:00 pm, whereas the longitude of Accra in Ghana is 0º and the local time is7:00pm?
Step 1: Calculate the difference in time
10:00pm - 7:00pm = 3 hours
Step 2: Find the difference in degree. Multiply the
x 15º * 3 hours
x = 45º
number of hours by 15
15º = 1 hour x = 3 hours
Since Morogoro is East of Ghana, the longitude of Morogoro is 45º E
Form 3
Structure of theearth
The earth’s crust, mantle andcore
Order of Layers -
Lithosphere - Contains thecrust
Mohorovic Discontinuity - Boundary between crust andmantle
Mantle - Contains the Asthenosphere
Gutenberg Discontinuity - Layer of rocks between mantle andcore
Core (Barysphere) - Contains inner and outercore
Sial and sima are the rocks that make up the outer crust of theEarth
Water Table - Is the level at which the groundwater pressure is equal to atmospheric pressure and is the upper limit of the saturation of water in a saturated rock
Asthenosphere - Is the region of the upper mantle of the Earth and balances the movements of Earths materials
Barysphere (Core) - Scientific name for the core, made up of iron and nickel
Conrad Discontinuity - Is the border between the upper continental crust and the lower one (sial and sima)
Core - Interior layer of the earth which is subjected to great heat and pressure
Gutenberg Discontinuity - The layer of rocks which separates the mantle from the core Hydrosphere - Is the combined mass of water found on, under, and over the surface of planet Lithosphere - The hardest part of the Earth’s crust (Litho means rock), geographical name of the crust Mohorovic Discontinuity - Is the boundary between the Earth's crust and themantle
Sial - Part of the Earth forming the upper part of the crust or continental blocks
Sima - The lower part of the Earth’s crust
Types of rocks of the earth’scrust
Conglomerate - Is a rock consisting of finer-grained materials that have become cemented together
Igneous Rock - Is formed through the cooling and solidification of magma or lava
Metamorphic Rocks - Are formed by the transformation of a rock by pressure and heat inside the Earth
Sedimentary Rocks - They are usually found in layers, important minerals can be found there, some are deposited by wind; they can be formed organically, chemically, or mechanically
Shale - A sedimentary rock composed of rounded gravel-sized particles
Examples of metamorphic rocks - Granite, slate, marble and gneiss
How sedimentary rock is formed - Formed by cementation and compaction of sediments arranged in layers by deposition
Features of sedimentary rocks - Usually found in layers, contain important minerals, can be deposited by water or wind, are formed organically/mechanically/chemically
Economic importance of rocks - Provide building material, used for industry, formation of soil, storage of underground water, provides fuel (coal), manufacturing of cement, salt extraction, decoration in houses
Economic significance of sedimentary rocks - Contain building material, used as decorative material, provide energy (coal), production of cement, formation of features in karst regions
Quartz is a compound element of silicon and oxygenGranite and basalt are examples of igneous rocksMarble is metamorphized limestone
The three main groups of rocks on the surface of the earth are igneous sedimentary and metamorphic and are classified according to how they were formed
Igneous rocks are formed when molten rocks from the mantle cool and solidifyClay is classified as an impermeable rock
Simplified geological time scale
Order of time periods of the geological time scale: Oldest
Paleozoic - Primaryperiod
Mesozoic - Middleperiod
Cenozoic - Modernperiod
Youngest
Cenozoic Era - The most recent of the three classic geological eras and covers the period from 65.5 million years ago to the present following the Mesoic Era
Geological Time Scale - Is a chart which is used to date rocks to understand how landforms were created
Forces that affect theearth
Forces causing earth movements 3.2.2 Internalforces
Internal forces operating in the Earth - Diastrophic forces
Radial/vertical and lateral/horizontalmovement
Features caused by faulting - Formation of rift valleys (graben), horsts, plateaus, basins, block mountains, fault scarps, tilt block landscape, changes drainage and causing of earthquakes, occurrence of springs River Valley (Graben) - Is a depressed block of land bordered by parallel faults. A graben is the result
of a block of land being downthrown producing a valley with a distinct scarp on each side. Graben often occur side-by-side with horsts
Horsts - Is the raised fault block bounded by normal faults or graben. A horst is formed from extension of the Earth's crust. The raised block is a portion of the crust that generally remains stationary or is uplifted while the land has dropped on either side
Plateau - An extensive elevated region with a gentle undulating surface with a uniform summit level
Spring - Is a natural occurrence where water flows to the surface of the earth from below the surface. Thus it is where the aquifer surface meets the ground surface. Forms from a dyke cutting across a layer of permeable rock
Aquifer - A natural outflow of water from the surface rock
Artesian Aquifer - Is a confined aquifer containing groundwater that will flow upward through a well, called an artesian well, without the need for pumping
Types of earth movements (caused by either compressional or tensional forces) - Vertical movements, lateral movements (orogeneses)
Types of folds - Symmetrical, asymmetrical, over fold
Symmetrical Fold - A fold produced with limbs of similar nature
Asymmetrical Fold - A fold where one limb is steeper than the other, they are not similar
Overfold - Fold formed when compressional forces push one limb of an asymmetrical fold over another
Types of faults - Normal faults, reverse faults, tear (transformation, shear) fault
Normal Faults - Produced by tensional forces
Reverse Faults - Caused by compressional forces
Tear Fault - A vertical fracture produced when two blocks slide against one another
Examples of fold mountains - Rocky mountains, Appalachian mountains, Alps, Andes, Atlas, Himalayas
How a graben (rift valley) forms - Is formed when faults between two rocks sink down due to either compressional or tensional forces
Anticline - Is a fold that is convex up and has its oldest beds at its core
Block Mountains - Are formed when large areas of bedrock are widely broken up by faults creating large vertical displacements of continental crust
Compression Forces - Causes a wrinkling of the Earth’s surface due to forces pushing towards each other Exfoliation Joints - Are surface-parallel fracture systems in rock often leading to erosion of concentric slabs Fault - Is a fracture in the crust due to stress or strain associated with rock displacement
Faulting - Is the fracturing of the crust to form faults
Folding - Is when one or a stack of originally flat and planar surfaces are bent or curved
Lateral Forces - When two forces act away from each other laterally
Joint - Is a crack in the rock due to stress but is not associated with rock displacement
Orogeny - Refers to forces and events leading to a severe structural deformation of the earth's crust due to the engagement of tectonic plates
Range - Chain of mountains bordered by highlands or separated from other mountains by passes or valleys
Set of fault types - Normal fault, reverse fault, tear (symmetrical) fault
Syncline - Is a downward-curving fold, with layers that dip toward the centre of the structure Tectonic Plates - Is a scientific theory which describes the large scale motions of Earth's lithosphere The difference between faults and joints is that joints have no associated displacement
Fold mountains are caused by compressional forces
Vulcanicity
Features with volcanicity - Caldera, craters, dyke, laccoliths, plug dome, solfatara, phacolith, lopolith
Caldera - A feature formed as a result of a violent volcanic eruption and is shaped like a large basin or depression on the top of a volcano
Dyke - A vertical feature formed out of the solidification of magma within the Earths crust, forms across a bedding plane of bedrock
Laccolith - Is a sheet igneous intrusion that has been injected between two layers of sedimentary rock Lopolith - Is a large igneous intrusion which is shaped like a lens with a depressed central region Phacolith - Lens-shaped strip of igneous rock formed if magma solidifies along anticlines or synclines Solfatara (Fumarole) - Is an opening in the Earth’s crust near volcanoes which emit steam and gasses
Features of intrusive vulcanicity - Dyke, sill, laccolith, Lopolith, Phacolith, batholith
Sill - Is a flat sheet intrusion that has intruded between older layers of sedimentary rock, beds of volcanic lava, forms along the bedding planes of bedrock
Batholith - A large mass of solidified rock formed when magma cools in the heart of mountain ranges
Major extrusive volcanic features - Caldera, crater, shield volcano, crater, ash and cinder cone (scoria cone), composite cone (strato-volcano), volcanic plug (plug dome volcano), acid lava cone
Crater - A depression formed on the summit of the cone after the plug has been blown off
Shield Volcano - A broad domed lava cone with gently sloping sides
Volcanic Plug - The solidified volcanic feature within the vent that prevents an eruption Ash and Cinder Cone - A cone shaped accumulation of rock fragments around a vent Composite Cone - A large cone with alternate layers of fragments from ash or lava
Acid Lava Cone - A dome shaped volcano with convex slopes formed when acidic lava solidifies around a vent
Minor extrusive volcanic features - Solfatara, fumerole, hot springs, geysers
Hot Springs - Spring caused by the emergence of heated groundwater from the Earth’s crust
Geyser - Is a spring with an intermittent discharge of water ejected violently and accompanied by a vapour phase (steam)
Types of volcanoes - Dormant, extinct, active
Dormant - A volcano which has stopped erupting but can still erupt at any time Extinct - A volcano which has stopped erupting and will not erupt again Active - A volcano with erupts frequently
Lava - Is molten rock expelled by a volcano during an eruption, is the name of magma on the surface Magma - Is a mixture of molten rock and solids that is found beneath the surface of the Earth Volcanic Eruption - The forceful emission of magma from the core of the Earth through a vent
Volcano - Is an opening, or rupture, in a planet's surface or crust, which allows hot magma, ash and gases to escape from below the surface
Volcanism - Refers to the range of processes by which molten material and gasses are either intruded into the Earth’s surface or extruded from the Earth’s surface
Characteristics of a shield volcano - Forms from fluid lava which flows to cover a large surface area, formed by basaltic lava, lava flow is slow, not very tall but occupies a large surface area, crater is small due to slow rate oferuption
A volcanic eruption is most likely to be violent if the lava reaches the surface through a fissure due to highpressure inside thevolcano
Earthquakes
Causes and effects of earthquakes - Causes: Tectonic forces (diastrophic forces), faulting of lithosphere, volcanism, mass movements, falling of meteorites, mans activities (e.g. quarrying, explosives), movements of large amounts of animals Effects: Death, destruction of property, formation of joints in the rocks, landslides, collapse of buildings, tsunamis, fires
Crest - The upper part of a wave
Earthquake - The sudden movement of the Earths crust along faulted and volcanic areas when tectonic plates collide with each other
Epicenter - Is the point on the Earth's surface that is directly above the focus
Focus - Is the point where an earthquake originates
Magnitude - Refers to the total amount of energy released by an earthquake
Mercalli Intensity Scale - Is a scale used for measuring the intensity of an earthquake Richter Scale - Measures the amount of energy released by an earthquake Seismography - Measures the intensity of an earthquake
Seismology - The study of the Earths movements such as earthquakes or tremors
Trough - The bottom part of a wave
Externalforces
External forces operating on the Earth’s surface - Exogenic forces, denudational forces
Mass wasting
Mass Wasting - Is the geomorphic process by which soil, regolith and rock move downslope under the force of gravity. Is caused by the process of granular disintegration, tips electric polls and fences
Eluviation - The process of the removal of materials from geological or soil horizons
Denudation - The process of rock disintegration by means of erosion, weathering, or mass wasting
Forms of slow mass wasting - Soil creep, talus (scree) creep, solifluction (sludging)
Soil Creep - Slow movement of soil particles which can be recognized by bending of trees and fences
Talus Creep - Very slow movement of waste rock of all sizes down a slope
Sludging - The gravitational flow of soil mixed with gravel saturated with water down a slope
Forms of rapid mass wasting - Earth flow, mudflow, avalanches, landslides, slumping, rockslide, debris slide, rock fall
Earth Flow - A downslope viscous flow of fine grained materials that have been saturated with water, and moves under the pull of gravity
Mudflow - The movement of large volumes of materials which are supersaturated with water as mud Avalanches - The sudden and catastrophic movement of materials down a slope with snow Landslides - Movements of materials which slip rapidly down a slope
Factors affecting mass wasting - Gradient(slope), climate, vegetation, nature of material and extent of saturation, endogenic forces (tectonic forces), human beings
Effects of mass wasting in our daily life - Death, loss of property, soil erosion, formation of fertile soil, creation of lakes, creation of tourist attractions, land degradation
Weathering
Weathering - The destruction of rocks by climatic conditions such as rain or temperature change
Types of weathering - Mechanical, chemical, biological (biotic)
Forms of mechanical weathering - Exfoliation, granular disintegration, block disintegration, shattering
Exfoliation - The peeling off of the outer layer of the rock due to high temperatures Granular Disintegration - The breaking up of rocks which consist of different minerals Block Disintegration - Takes place when a homogeneous rock breaks into blocks due to
temperature, common in rocks that are well jointed
Frost Shattering - Freezing and thawing causes the rocks to expand and contract until they break
Types of chemical weathering - Oxidation, carbonation, hydration, hydrolysis, solution
Oxidation - The process where minerals are oxidized when they combine with oxygen and water
Carbonation - Takes place when a weak acid in rainwater reacts with rocks composed of calcium carbonate such as limestone
Hydration - When certain minerals absorb water and swell causing fracturing of the rock
Solution - The process where some soluble minerals dissolve e.g. rock salt
Factors affecting the rate weathering - Nature of the rocks, climate, organisms, relief(slope)
Nature of the rocks - Mineral composition, rock structure, colour
Climate - Climatic variations increase or decrease the rate that rocks weather Organisms - Plants and animals can break apart rocks chemically or mechanically Relief - Steeper slopes can cause rocks to break apart
Chemical weathering is the result of organic acid and weak carbonic acidChemical weathering is most effective when it is hot and wet
Tors - Rock outcrops formed by weathering which is usually found on near the summit of a hill, formed when joints develop in rocks
Wind Attrition - The process by which rock particles rub or collide against each other when they are carried along with the wind
Wind Deflation - The process by which the wind blows away loose rock waste and in doing so, lowers the desert surface producing depressions
Wind Abrasion - The process by which small particles of rock are hurled by the wind against rock surfaces to blast away features
Erosion and deposition by water, ice, wind and wave action Water
Types of deserts - Sandy, rocky (erg), badlands, mountainous
Erg - A stony desert
Depositional features due to water action in deserts - Alluvial fans, alluvial cones, bajadas (bahada), peripediment, playas (sebkhas/chotts) and Salinas(salars)
Alluvial Fans - Fan-shaped features formed when large quantities of sediments are deposited at the foot of steep slopes
Alluvial cones - Look like alluvial fans but consist of coarser material
Bajadas - Continuous gently sloping features with an undulating surface formed when alluvial fans/cones coalesce during the deposition of more sediment at the foot of a steep slope
Playas/Salinas - Are temporary salt lakes
Peripediment - A gentle slope formed when alluvial deposits overlie the edge of the pediment surrounding the playa
Erosional features due to water action in deserts - Rills, gullies, wadis (chebka), pediment, pediplains, inselbergs, mesas, buttes, dry river valleys
Rills - Small, shallow grooves formed due to erosion by surface runoff
Gullies - Deep, steep troughs produced when erosion in rills becomes larger
Wadis - Steep-sided, deep and flat floored valleys formed due to severe erosion by water in the desert
Pediment - Gently sloping platform formed when the edges of the desert and semi-desert highlands get pushed back by erosion and weathering
Pediplains - Multi-concave features resulting from the coalescing of several adjacent pediments
Mesas - Extensive flat-topped residual tablelands with resistant rock on the top
Buttes - Small but prominent residual flat-topped hills capped with resistant rock which remain after denudation of a plateau in arid areas
Dry River Valleys - River valleys which remain dry after streams of water dry during the dry season
Surface features of a karst region (limestone surface features) - Scarps, hills and mountains, grikes (grykes), clints, swallow holes (sink holes or ponor), doline, uvala, polje, gorge, terra rosa
Terra Rosa - A red clay which is found in floor of a polje
Scarps/Hills/Mountains - Formed when there are hard rocks which have not been eroded away that remain standing as residual features
Grikes - Gullies formed when water erodes the cracks on the surface before going underground
Clints - Ridges or blocks in limestone rock separating grikes in a karst region
Sinkhole (Swallow Hole) - A vertical hole produced when the joints are enlarged by water percolating into the rock
Doline - Is a large depression produced when several swallow holes coalesce (join together)
Uvala - Is a large depression formed when Dolines coalesce
Polje - A very large depression formed when several uvalas collapse
Gorge - Steep sided trough lined by steep rocky cliffs which form when the roof of the cavern collapses
Karst - A well developed surface of a limestone region where the rocks are well jointed
Limestone - A soluble rock with jointed structures resembling a wall
Underground features of a limestone area (caves) - Caverns, stalactites, stalagmites, underground river, natural pillar, anthodites, resurgent river
Caverns - Underground chambers formed due to the solution of limestone rock underground Stalactite - Long needle like calcite rock that hangs downward from the roof of a limestone cave Stalagmite - Is a type of structure found on the floor of a limestone cave due to the dripping of
mineralized solutions and the deposition of calcium carbonate
Underground River - The river formed when water sinks underground through sinkholes and joints
Natural Pillar - A natural column formed when a stalactite and stalagmite join together or when a stalagmite reaches the roof
Anthodites - Delicate flower-like formations which are formed when calcite is deposited on the roof of caverns
Resurgent River - An underground river that reappears on the surface somewhere
The amount of water that sinks into the ground from the surface depends on the underlying geological structure
Erosional features in the upper section of a river (young stage, river torrent, or river mountain) -
V-shaped valley, interlocking spurs, river capture, waterfalls, canyons(gorge), rapids, pot holes, plunge pool, boulders
V-shaped Valley - A valley with a strong gradient which is formed due to the river’s high velocity
Interlocking Spur - Is a natural geographical feature which occurs in a river's upper course, where vertical erosion is the dominant force in determining the river's course
River Capture - Process where a stronger river captures a weaker river when the stronger river erodes its valley both vertically and headword at a faster rate and flows at a lower level than the weak river
Waterfalls - Sudden downpours of water along a river due to the sudden drop of slope in the riverbed
Canyon - A deep ravine cut between cliffs like mesas, buttes, or plateaus by a river in a desert climate
Rapids - The sudden descent of the stream of water without a waterfall, the slope is not steep enough Pot Holes - Shallow depressions cut by pebbles as they are carried by swirling water on the riverbed Plunge Pool - A large deep depression that develops at the base of waterfalls due to abrasion by
pebbles carried in the river
Boulders - Large rocks broken up by river erosion that are too heavy to be taken downstream
Features resulting from river capture - Elbow, pirate river, wind gap, misfit river
Elbow - The bend produced where the river has been diverted
Misfit River - Stream which lost headwaters due to its volume being capture by another river
Wind Gap - The valley behind the misfit river in between the misfit river and the elbow
Pirate River - The river which takes volume from the misfit river and is rejuvenated in the process
Features in the lower section (old stage, or flood plain of the river) of a river (depositional features) -
Flood plain, natural levees, ox-bow lakes (Cut-offs), deferred tributary, deltas, estuaries
Flood Plain - A gently sloping area produced as a result of deposition of alluvium (silt and sand)
Levee - Embankments produced as the result of deposition of sediments along the bank of the river in the flood plain. Also created by humans to prevent flooding
Ox-bow Lakes - Cut-off meanders formed as the river cuts through the necks of the loops or well established river bends
Deferred Tributary - A tributary in the lower course of a river that has been forced to flow alongside the main valley before joining the river
Deltas-Lowlying swampyplainformedastheresultofaccumulationofalluviumatthe mouthofariver
Estuary-Rivervalleythathasbeendrownedbya riseinsealevel orthefallofthelandalong thecoast
Basin lakes of Africa - Victoria and Chad
Types of river rejuvenation - Dynamic rejuvenation, static rejuvenation
Dynamic Rejuvenation - Rejuvenation brought about by either sea level change or land level change
Static Rejuvenation - Is the type of rejuvenation caused by the increase in the river volume due to heavy rainfall, melting of ice or river capture
Features due to river rejuvenation - Knick point (rejuvenation head), paired terraces, incised meanders Knick Point - Break of the slope in the long profile of the river valley where the riverbed drops sharply Paired Terraces - Steps or benches on either side of a river valley formed as a result of undercutting of
the river due to renewed erosion
Incised meanders - Steep sided curved bends of the river valley produced as a result of the undercutting of the riverbed by the river along the meander
Rejuvenation - The renewed activity of an ecological area such as a river or forest
Types of drainage patterns - Dendritic pattern, trellised pattern (rectilinear pattern, rectangular pattern, radial pattern, annular pattern, centripetal pattern, and parallel drainage pattern
Dendritic Pattern - Looks like a tree trunk with its branches as veins, possessing many tributaries
Trellised pattern - Develops in areas with alternating hard and soft rock, the tributaries join the main river valley at almost right angles
Rectangular Pattern - Its tributaries join the main river at a right angle
Radial Pattern - The drainage pattern where streams flow outwards down flanks or slopes of a dome or cone such as a volcano e.g. Kilimanjaro
Annular Pattern - A series of streams flowing in a spiral way forming concentric circles Centripetal Pattern - Streams flowing from all directions converge at the center in the basin Parallel Drainage Pattern - A series of streams running parallel to one another
Types of drainage systems - Accordant drainage system, discordant drainage system
Accordant Drainage System - The normal drainage system of a river, the water flows in accordance to rock structure and slope
Discordant Drainage System - Does not flow in accordance with rock structure or slope
Accordant drainage systems are seen by the following drainage patterns - Radial, trellised, rectangular, centripetal drainage patterns
Discordant drainage systems - Antecedent, superimposed, anteposition
Antecedent - A river maintains its course by eroding vertically up the land due to having enough velocity to go up the slope
Superimposed - The opposite of an antecedent, the river maintains its course into a newly exposed rock layer without following the structure of the rock
Anteposition - Develops as a result of the combination of antecedence and superimposition
Alluvium - Loose soil or sediments, eroded, deposited, and reshaped by water on Earth’s surface
Deposition - The laying down of rock particles on the surface
Importance of rivers - Water supply, transport, hydroelectric power, sources of materials like sand/diamonds, fishing grounds, tourism, irrigation
Causes of river rejuvenation - A fall in the sea level (eustatic change), land uplift and subsidence (isostatic change), increase in the river volume (discharge)
Conditions necessary for the growth of coral polyps:
Warm waters with temperatures between 20-30 degrees Celsius
Clear salty water, hence they do not occur at rivermouths
Sunlight that penetrates to a depth of about50m
Plentiful supply of plant food andoxygen
Types of coral reefs - Fringing reef, barrier reef, atoll
Fringing Reef - A reef attached to the coast with a shallow lagoon separating it from the mainland
Barrier Reef - Similar to a fringing reef but the barrier reef is farther away from the coast and is separated from the mainland by a larger deeper lagoon
Atoll - Circular or elliptical shaped coral reef enclosing a lagoon found in mid oceans
Features of an ocean floor - Continental shelf, continental slope, trench, plateau, basin, plain, deeps
Ocean Ridge - Is an underwater mountain range, typically having a valley known as a rift running along its spine, formed by plate tectonics
The continental shelfis the best place for commercial fishing
Attrition - Collision of loads with each other and broken down in a river
Cross profile of a river - Distance between one side of a river and the next Dendritic Drainage - A drainage pattern which looks like a tree with its branches Drainage Pattern - Is the plan or layout of the river with its tributaries Formation of a river delta - First corrasion, then transport, thendeposition
Hydraulic Action - Wearing away of the sides and bottom of a river’s channel by the load carried by a river
Long profile of a river - Stretch of the river from its source to its mouth
Meander - Is the bend in a river as it courses downriver
Potholes - Is a type of disruption in the surface of a roadway where a portion of the road material has broken away, leaving a hole
River Rejuvenation - Is the renewal of the erosive activity of a river in its valley
River Valley - A section of a river where erosion is pronounced and is characterized by a V-shaped valley The source of a river is the catchment area
The erosive power of a river depends mainly upon its volume and speedRiver water can flow in the following two ways: Laminar and turbulent
Waves
Features due to wave deposition - Spit, tombolo, sand bar, mudflats, beaches, berms, cusps
Spit - A low narrow ridge of sand attached to the land at one end with the other side ending in the sea
Tombolo - Is a deposition landform in which an island is attached to the mainland by a narrow piece of land such as a spit or bar
Mudflat - Are coastal wetlands that form when mud is deposited by tides or rivers. They are found in sheltered areas such as bays, bayous, lagoons, and estuaries
Beach - Lies between the high and low water levels (tides), formed by deposition of sand along water Berm - A narrow ridge or shelf with a steep front which is found on the upper part of some beaches Cusps - A series of small, horn-shapes projections separated by shallow indentations that face
seawards giving the beach a curved appearance
Sand Bar - A ridge of material which lies parallel or almost parallel to the coast or across the estuary or bay between two headlands
Features due to wave erosion - Cliffs, wave-cut platforms, bays, caves, blowhole (gloup), arch, geo, stack, stump, headland
Cliff - Is a high perpendicular or steep rock face along a sea coast produced by waves below
Wave-Cut Platform - A plateau like structure produced by continual undercutting of a cliff by waves
Headland - Is a high promontory with a steep face which projects into the sea or a lake when less resistant rocks are eroded away
Bays - A curved indentation of the sea into the land which is formed by the erosion of less resistant rock
Cave - Is a tunnel-like opening at the base of a cliff face that forms where there is a weakness in the rocks (joint or fault) through constant wave erosion by abrasion and hydraulic action
Arch - Is a roof-like structure formed as a result of a headland being eroded right through from one cave to the other side of the headland
Stack - Is an isolated mass of rock near a coastline detached from the mainland by wave erosion which caused the collapse of an arch
Stump - Is an isolated mass of rock which was formed as a result of a stack being considerably eroded
Blowhole - Is a hollow structure nearly vertical on the land formed when erosion occurs along a vertical joint which passes from the land surface to the cave roof
Geo - A long narrow inlet of the sea, penetrating cliffs that have been formed as the result of the collapse of the roof joining a cave and blowhole
Shore - The land between the high tidal water level and the low tidal water levels
Shoreline - The line where the shore and sea meet
Classification of Coasts - Submergent coasts, emergent coasts, stable coasts, compound coasts Submergent Coasts - Result from the rise of the sea level or submergence of land Emergent Coasts - Result from the fall in sea level or uplift ofland
Stable Coasts - Coasts formed where there is little change
Compound Coasts - Produced from the mixture of emergences and submergences
Types of submerged upland coasts - Ria coasts, fiord coast, dalmation coasts (longitudinal coasts)
Ria Coast - Formed when the highland area with river valleys is submerged and the lower parts of its river valleys become flooded by water from the sea
Fiord Coast - Formed when glaciated U-shaped valleys are flooded after the submergence of the former coastal highland area
Dalmation Coast - Form where a mountainous area which lies parallel to the coast is submerged, forms valleys called sounds
Lakes
Classification of Lakes - Created by diastrophic movements, volcanic activity, erosion, deposition, man
Lakes caused by diastrophic movements - Rift valley lakes, down-warped lakes
Rift Valley Lakes - Formed when water occupies rift valleys formed as a result of faulting
Down-Warped Lakes - Formed when water occupies basin-like depressions
Lakes due to volcanic activity - Crater and caldera lakes, lava dammed lakes
Crater and Caldera Lakes - Formed when water occupies a crater or caldera
Lava Dammed - Formed when a river is blocked by lava that erupts and runs across the river
Lakes due to erosion - Glacial lakes, trough lakes, rock basin lakes
Glacial Lakes - Tarn lakes formed when water fills land occupied by cirques
Trough Lakes - Lakes formed when water occupies hollows on the floor of U-shaped valleys
Rock Basin Lakes - Formed when water occupies the depressions formed on the rock surface
Lakes due to deposition - Glacial depositional lakes, moraine dammed lakes, kettle lakes, ox-bow lakes, delta lake, flood plain lakes, marine deposition, lucastrine
Lucastrine - A delta which is found in a lake
Lakes which occur as a result of deposition - Playa, Ox-bow, Delta, Lagoon
Playa - Is a desert basin with no outlet which periodically fills with water to form a temporary lake
Ox-bow Lake - Is a waterhole that forms at the lower side of the river, where the river develops meanders while deposition is taking place
Delta - A broad tidal channel where a river enters the sea
Lagoon - Is a body of shallow sea water separated from the sea by some form of barrier Lake - Is a hollow or depression on the Earth’s surface where water has accumulated Manmade Lakes - Are formed as a result of the construction of a dam across a river
Ice
Sapping - The breaking of rocks by the alternation between thawing and freezing of water at the bottom of cracks in glaciated land
Erosional features formed in a glaciated highland - Truncated spur, U-shaped valley, pyramidal peak, arête, cirques (corrie/cwm), hanging valley, fjord, ribbon lake
Pyramidal Peak - Mountaintop that has been carved by ice during glaciation and frost weathering
Cirque (Corries) - Circular depressions which are formed by glaciations in the highlands
U-Shaped Valley - A steep-sided, flat bottom, wide valley which contains features produced by both glacial erosion and deposition
Arête - A steep ridge separating two cirques which is formed by cutting back of the walls of cirques Truncated Spur - Spurs whose ends have been cut off due to erosion as ice moves down the valley Hanging Valley - Is the tributary valley of the U-shaped valley which hangs above the floor of a U-
shaped valley separated by an almost vertical slope. If there is a river a waterfall will form
Fjord (Fiord) - Is a submerged glaciated U-shaped valley formed when the glacier has eroded its path by undercutting and been plunged into the sea
Ribbon Lakes - Lake that occupies an elongated trough excavated by ice in a U-shaped valley
Tarn Lake - Is a mountain lake or pool, formed in a cirque excavated by a glacier
Erosional features formed in a glaciated lowland - Eroded plain, crag and tail, roche mountonée
Eroded Plain - Is a rounded topography with a large area of bare rock scratched by boulders embedded in the base of the glacier
Crag and Tail - Is a resistant mass of rock standing in the path of a moving glacier
Roche Mountonée - Outcrop of resistant rock smoothed by a glacier into a gentle slope
Depositional features of a glaciated lowland - Till plain (boulder clay plain), drumlin, erratics, kames, eskers, kettles, moraines, outwash plains, kame-terrace
Till Plain - A long plain made of clay and boulders deposited by ice sheets and glaciers over a surface which contains features like erratics, drumlins, kames, eskers and kettles
Kettles - Are the depressions formed after the melting of the ice block enclosed within the till
Erratics - Are large boulders deposited by a glacier or ice sheets as they melt Drumlin - Elongated egg-shaped hills made of boulder-clay which occur in groups Moraines - Refer to the boulder clay deposits laid down in the lowlands to form ridges
Lateral Moraine - Lines of glacial deposits along the sides of valleys
Medial Moraine - Consist of rock fragments deposited in the middle of the valley which marks the point where two glaciers met
Terminal Moraine - Refers to the ridge like feature found at the end of a glacier
Recessional Moraines - Series of parallel terminal moraines that mark the retreat of glaciers
Esker - Is a long winding ridge of stratified sand and gravel
Kame - A feature of an irregular undulating mound of bedded sands and gravel
Kame-terrace - Is a discontinuous ridge along the valley side formed by deposition of sands in narrow lakes between a glacier and the adjacent rock wall
Outwash Plain - Is a wide gently sloping plain formed as the result of deposition of material by melt- water from the glacier
Wind
Erosional features due to wind in deserts - Rock pedestals, zeugen, yardangs, blowouts (deflation hollows/pans), inselbergs, desert pavements, ventifacts (draikanter)
Rock Pedestals - Tower like structures composed of alternate bands of soft and hard rock formed due to wind abrasion in the desert
Zeugen - Ridges consisting of alternate layers of hard and soft rock formed in areas where rock layers lie horizontally and are characterized by joints
Yardangs - Are the ridges consisting of hard and resistant rock bands standing either vertically or at an angle which run parallel to the direction of the prevailing wind
Blowouts - These are hollows or depressions produced by wind deflation
Inselbergs - Residual hills consisting of hard and resistant rocks left behind after the rest of the surface has been eroded away
Desert Pavements - The horizontal areas of bare polished rock formed by the scouring action of quartz
Ventifacts - Heavier rock blocks left behind after wind has carried away all of the material
Wind depositional features associated with deserts - Sand dunes, seifs, barchan, ripples, loess
Sand Dunes - Are hills of sand which have been deposited by the wind in a desert
Seifs - Are long narrow ridges of sand which lie parallel to the direction of the prevailing wind
Barchans - Crescent shaped sand dunes that are formed by an obstacle in the desert like a rocks
Loess - Are a sediment formed by the accumulation of wind-blown particles that were carried by the wind beyond the desert limits
Ripples - Small wavy structures commonly found between sand dunes
Formation of sand dunes (or barchans and seifs) are influenced by - The extent of vegetation cover, the size of the sand particles, the relief of the desert, the velocity of the wind
Artificialforces
Soil
Soilformation
Soil - A natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics
Processes of soil formation -
Weathering of rock to produceregolith
Regolith - Loose broken material due to weathering of rock or deposition of alluvium, drift loess and volcanic material
Formation of topsoil by adding water, gasses, living organisms, and decayed organic matter(humus)
Five major factors of soil formation - Time, parent materials, climate, living organisms, topography
Soil composition andproperties
Components of soil - Organic matter (biota, 45%), inorganic matter (5%), soil water (25%), soil air (25%) Organic Matter - Made of decomposed plant and animal remains (humus) and living micro-organisms Inorganic Matter - Provide minerals required for plant growth
Soil Water - Derived from rainfall and is important for regulating temperature, dissolving nutrients
Soil Air - Plants and animals gain oxygen for metabolism from soil air
Soil profile and characteristics
Characteristics of soil are influenced by- Vegetation, parent rock, climate and weathering
Propertiesofsoil-Soilprofile,soildepth,soilcolour,soiltexture,soilporosity,soilstructure
Soil Profile - A vertical cross-section of the soil showing its horizons
Soil Depth - Varying properties depending on the maturity of the soil and nature of rocks below
Soil Colour - Colour is determined by mineralogical composition of the soil
Soil Texture - The degree of coarseness or fineness of a soil
Soil Porosity - Total volume of pores or empty spaces between particles of soil material
Soil Structure - Refers to the arrangement of soil particles
Sources of soil pollution - Atmosphere, daily human activity, industrial activity, farms
Atmosphere - Pollutants introduced through acid rain
Daily Human Activity - Garbage like plastic, metals, bottles, cans are dumped on the soil Industrial Activity - Chemicals, radioactive materials and industrial waste are dumped Farms - Pesticides (DDT/fertilizers) and certain crops can damage the soil
Ways you can combat soil degradation - Good agricultural practices, mixed farming, crop rotation,avoid soil pollution, education of land users, avoid bush fires, ensuring soil moisture, avoid mass wasting Factorsinfluencingsoilfertility-Presenceofmineralplantnutrients,presenceofwater,presenceofair,
soil pH, soil, presence of colloids, presence of organisms
Loss of soil fertility - Leaching, over-cultivation, monoculture, soil pollution, soil erosion, mass wasting, loss of water in the soil
Simple soilclassification
Podzol - The group of soils which occur mostly in moist cool temperate climates
Clay Soil - Is a naturally occurring material composed primarily of fine-grained minerals
Humus - Refers to any organic matter that has reached a point of stability, where it will break down no further and might, if conditions do not change, remain essentially as it is for centuries, if not millennia
Laterites (Red Lateric Soil) - Are soil types rich in iron (causing red from oxidation) and aluminum, formed in hot and wet tropical areas
Leaching - Is the loss of plant nutrients from the soil, contributes to groundwater contamination
Loam - Is soil composed of sand, silt, and clay in relatively even concentration (about 40-40-20% concentration respectively)
Residual Mountains - Owe their origin mainly to denudation
Mulching - The practice of covering the soil with a layer of grass or plant remains
Advantages of mulching - Helps to conserve moisture in the soil by preventing evaporation, reduces loss of soil by erosion, rotting mulch adds organic matter to the soil, helps control the spread of weeds
Types of soil - Azonal, intrazonal, zonal
Azonal Soil - Are without well-developed characteristics due either to their youth or to some condition of relief or parent material which prevent soil development, Soils forming in recent eolian, alluvial and colluvial deposits are azonal
Intrazonal Soil - Have well defined soil profile characteristics that reflect the dominant influence of some factor of relief or parent material over the classic zonal effects of climate and vegetation
Zonal Soil - Soils with clearly distinguishable horizons which occur in definite regions of climate and vegetation
Soilerosion
Soil Degradation - Is the spoilage of the quality of soil through human activity. It is deterioration of the soil quality through loss of fertility, soil pollution, soil erosion and mass wasting
Soil Erosion - Is the physical removal of soil from one place to another by agents of erosion such as running water, wind, glacier, or waves
Soil erosion is caused by manmade and natural causes such as - Sheet erosion, gully erosion, splash erosion, rill erosion, climate, nature of soil, vegetation cover, topography, cultivation, excessive mining, construction activities, excessive deforestation by man, bush burning
Ways of preventing soil erosion - Contour farming, crop rotation, terrace farming, afforestation and reforestation, destocking, avoiding bush fires, growing cover crops
Ways to manage soil effectively - Education, training of farmers, planting better crops, afforestation/reforestation, reducing chemical use in farming/industry, recycling
Elementary surveying and mapmaking
Meaning and types ofsurvey
Forms of surveying - Chain/tape, prismatic compass, plane table, leveling, cadastral, geodetic
Chain Surveying - Is a method of plane surveying which deals with the measurement of linear horizontal distances. The distances covered in chain surveys are normally short and straight
Plane Table Survey - Is the science of measuring and fixing positions of distant objects by intersectionby considering the surface of the earth to be a plane (completely flat surface), curvature is ignoredPrismatic Compass Survey - Is the fixing of an objects position in the field by measuring the angles of
bearing between the line of magnetic north and the line of sight of the object
Leveling - Is the process of measuring height differences between points on the ground by determining the relative altitudes of the two points
Cadastral Surveying - The kind of survey which collects data about the ownership of property
Geodetic Surveying - Precise type of surveying which covers large areas considering the curvature of the earth, uses triangulation/traversing/trilateration/leveling/astronomical direction fixing
Leveling - A process of determining the differences in elevation between two points
Uses of leveling - Construct contour maps, find the best level at which you should erect a building, create longitudinal section of roads/railways/canals/pipes/sewers in urban areas, determine proper human settlements
Tools used for leveling - Leveling instruments (i.e. theodolite, abney level, clinometer, alidade, dumpy level, tilting level etc), leveling staff, chain or tape, pegs, field sheets
Purpose of plane surveying - Determine horizontal distances between two or more points on the surface, to locate physical and nonphysical features on the surface, direction of various features of the surface, determine the area of a given region
Tools for a plane table survey - Plane table, alidade, plumb bob, trough compass, spirit level, clinometer
Advantages of a plane table survey - It is the best kind of survey used to measure and fix positions of distant objects, it is quick/accurate and allows quick sketching of details, it can cover very large land areas, less accumulation of errors than chain surveying, uses instruments which are easy to use, useful for cartography, booking is not required
Disadvantages of a plane table survey - Not suitable for a small area of land, not suitable for undulating surfaces, cannot be used during damp or rainy seasons, requires alidade which requires skills to use, a simple math error can cause all angle measurements to be incorrect, some instruments are expensive
Equipment used for prismatic compass surveying - Two prismatic compasses, ranging poles, tape measures, chains, metal markers, chalk, field sheets
Advantages of prismatic compass surveying - Rapid method, check can be made on all compass bearings, cumulative error is reduced/easily fixed, objects can be pin-pointed with accuracy, method can be combined with other methods
Disadvantages of prismatic compass surveying - Transport is needed if surveying over long distances, human error is involved in observations, magnetic rocks may affect readings
Alidade - Is a device that allows one to sight a distant object and use the line of sight to perform a task such as to draw a line on a plane table
Surveying - The science of measuring and recording distances, angles and heights on the Earth’s surface to obtain data from which accurate plans and maps are made
Topographic Maps - colour contour maps showing the physical and manmade features such as rivers/roads/mountains/valleys/railways
Traversing - Consists of a series of lines whose lengths and directions are measured, connecting points whose positions are determined used to establish data benchmarks
Triangulation - Consists of a series of connected triangles which overlap each other, used to reduce the number of measurements that need to be taped or chained
Trilateration - Is the use of electronic distance measuring equipment to directly measure the lengths of the sides of triangles from which angles can be calculated
The three types of topographic surveying are chain surveying, prismatic compass surveying, and plane tablesurveying
Bearing - The direction of a place in degrees from another place
Bearing of SW is - 225º
ESE - 112.5 º
Chainsurvey
Instruments used in chain surveying - Chain, tape, surveyor’s band, ranging poles, cross staff, pegs, arrows, optical square, notebook
The Chain - This chain is made up of pieces of steel which are connected by rings
The Tape - Used to measure horizontal distance on the ground
Surveyor’s Band - A long graduated strip made from steel or plastic, rolled in a metal frame
Ranging Poles - Locates a place temporarily during the chaining process
Cross Staff - Used to set a perpendicular line or right angles from the main line of survey
Pegs - Their major function is to mark points permanently on the ground
Arrows - Steel skewers which mark and locate temporary positions on the surface Optical Square - Used for setting offsets from right angles from the line Notebook - Good notebook for recording or booking all fieldworkinformation
Preparing a chain survey - Must be well informed about the nature and location of the area, land configuration, presence of buildings or natural obstacles, preparation of instruments and personnel, prepare working schedule,transportation
Advantages of chain surveying - Used to map small areas on flat ground, simple to conduct, used to add details to existing maps, needs few people to set up, uses simple tools like pegs, applicable to compass surveying also, only survey for measuring distances (the others measure angles and heights), does not require a lot of mathematicalcalculations
Disadvantages of chain surveying - Time consuming, subject to the accumulation of errors
Map reading andinterpretation
Concept of mapreading
(Not in study guide)
Reading and interpreting topographicalmaps
(Not in study guide)
Photograph reading andinterpretation
Types of photographs
(Not in study guide)
Reading and interpretingphotographs
(Not in study guide)
Application ofstatistics
Concept ofstatistics
Importance of studying statistics - It helps to summarize massive data in simple figures, simplifies the process of data interpretation, helps to represent data in visual ways like charts and maps
Sources of Data - Primary sources, secondary sources
Primary Data Sources - Data collected directly from the field, also known as first hand data
Secondary Data Sources - Data obtained from other people’s findings i.e. from books, journals etc
Continuous Data - Are number that can be expressed with infinite figures of possible values that fall between any two observed values
Data - Exact numerical values collected and arranged for a certain purpose
Discrete Data - Consists of separate and indivisible categories of data
Group Data - Are values given in a range of numbers, data falls into certain classes
Single Data - Are statistics or values given for each individual item in a sample
Simple statistical measurement andinterpretation
Use the following data to draw a group bargraph:
Contribution of Agriculture to the Gross Domestic Product (GDP) in East Africa (in percentage)
Year
Tanzania
Kenya
Uganda
1954
64
47
67
1958
59
42
64
1960
61
40
61
1965
54
38
59
To draw this graph you must first think about what the x and y axes will be. The x axis will be years because this will group together the percentages from each country. The y axis will be percentage because this is the value being compared between the various countries. A grouped bar graph is chosen because it shows the difference between each country’s GDP by year clearly.
Advantages - Enable easy comparisons, easy to interpret, no complicated calculations, detailed, contrasts clearly, gives visual impression about thetotality
Disadvantages - Consumes time, does not give accurate impression of totals, erroneous conclusions can be made depending on the scale used, uses manycolours
Use the data below to draw a compound line graph and a compound bargraph
Year
Maize
Coffee
Beans
Sorghum
Wheat
2001
300
550
720
800
850
2002
290
540
530
810
830
2003
310
520
650
750
780
2004
250
530
660
700
770
2005
270
525
700
800
850
To draw a compound line graph you first plot the x and y axes. You start with the smallest number to draw the bottom portion of the graph (in this example it is maize), then you choose the next lowest until you have drawn a line for each variable. After this you shade down to the next line until you have completed
Advantages of compound graphs - Useful in comparing many variables, attracts readers with colours, detailed information is provided
Disadvantages of compound graphs - Needs knowledge of mathematics, needs more time to construct, if the same shading is used it may mislead the interpreter
Use the data below to show the enrolment of form 5 students using a divergent line and bargraph
Year
Number of students
1980
100
1981
150
1982
175
1983
200
1984
225
1985
300
To construct a divergent line or bar graph you must first calculate the mean deviations. This is done by calculating the mean then finding the difference between the number of students and the mean deviation.
Finding the mean deviation Step 1: Find the mean
100 150 175 200 225 300
Mean (average) =
191.7
6
Step 2: Find the deviation for each data
Ex. 1981
Ex. 1983
150 - 191.7 = -41.7
200 - 191.7 = 8.3
Year
No of Students
Mean Deviation
1980
100
-91.7
1981
150
-41.7
1982
175
-16.7
1983
200
8.3
1984
225
33.3
1985
300
108.3
Since the answers are both negative and positive (because they lie on either side of the mean), you will use a graph that shows both positive and negative values, the divergent bar graph. You can also use a line graph, or a simple bar graph.
Advantages: It shows the increase or decrease of values over time, it is used for comparisons
Disadvantages: It does not deal with real numbers but rather only with mean deviations, it also needs extra calculations and is difficult to construct
Construct a line graph and bar graph from the data below and discuss the definition of a line graph as well as its maintypes
Line Graph - Is a graphical representation of data which uses a line to join the points of the data being represented
Four types of line graphs - Simple line graph, compound line graph, group line graph, convergent line graph
Year
1970
1971
1972
1973
1974
Coffee Production (Tons)
2050
2600
1800
1950
3000
Advantages - Easy to construct/draw, illustrates variations, no difficult calculations, easy to interpret/read, saves, simple visual impression, wide variety of uses, exact values are easily estimated
Disadvantages - Inaccurate deductions can be made, easy to confuse X and Y variables, little space where X and Y axes meet, cannot represent more than one item
Create a pie chart using the data below of car types used inTanzania
Period
Datsan
Land rover
Isuzu
Toyota
Others
8:30-10:30 AM
100
150
300
240
80
2:30-4:30 PM
40
60
70
20
50
6:30-8:30 PM
120
130
90
140
120
Total
260
340
460
400
250
To create a pie chart you must calculate the degrees that each portion of the pie represents
Step 1: Calculate the sum total of angles. Add up the values in the Total row.
260 + 340 + 460 + 400 + 250 = 1710
Step 2: Calculate angles of each car type and then draw them with a protractor
Ex. Datsan
260 * 360º 54.7º
1710
Advantages - Easy to interpret, easy to construct, illustrates statistical information accurately, gives a good visual representation, useful for comparing various commodities/sectors/items
Disadvantages - Difficult to read for getting exact values, trends and directions of change in value cannot be deduced from a pie chart, time consuming to calculate and construct, difficult to interpret or draw when there are numerous items
Make a population pyramid graph from the followingdata:
Simply plot males on one side and females on the other with each row of the graph representing one of the columns of data. On the X axis you start with 0 in the centre and write marks on either side of it.
Age
0-4
5-9
10-
14
15-
19
20-
24
25-
29
30-
34
35-
39
40-
44
45-
49
50-
54
55-
59
60+
Male
6000
5000
4000
3700
3500
3400
3200
3100
3000
2800
2400
2000
1700
Female
6000
5800
4500
4200
4000
3900
3700
3600
3500
3200
3000
2500
2200
Advantages - Enables one to analyze the structure of a given population, forms a basis for predicting population structure in the future, used to estimate or evaluate current/future needs, easy to construct and interpret, used to compare structure of different populations, used to compare between males and females
Disadvantages - Involves a lot of calculation, not easy to choose convenient horizontal scales, five year age groups generalize groups, can take a lot of space if there are too many age groups
a) From the data below calculate the mean, mode, median, modal class, and standarddeviation
8, 22, 18, 20, 22, 8, 8, 13, 16, 21, 22, 30, 23, 16, 8, 4, 6, 2, 10, 12, 14, 15, 16, 22, 22, 27, 26, 22, 18, 4
First order all of the numbers
2, 4, 4, 6, 8, 8, 8, 8,10, 12, 13, 14, 15, 16, 16, 16, 18, 18, 20, 21, 22, 22, 22, 22, 22, 22, 23, 26, 27, 30
Finding the Mean (Average) Step 1: Sum all numbers
nums 475
Step 2: Divide by number of values
Number of values = 30
Step 3: Divide sum by number of values
475 15.8
30
Finding the Mode
Step 1: Find the value with the highest frequency
Mode = 22, it was found 6 times
Finding the Median
Median - The median is the number which divides the distribution of numbers into two equal parts (halves)
Solution: Since there are 30 numbers, the middle value is in between the 15thand 16thnumbers, so you must find the average of these two values. In this case the 15thand 16thvalues are the number 16
16 16 16
2
Mean (Avg) = 15.8 Mode = 22
Median = 16
b) Finding the modal class and standard deviation for the above set ofnumbers
Class Interval
F
X
F * X
X2
F*X2
0 - 4
3
2
6
4
12
5 - 9
5
7
35
49
245
10 - 14
4
12
48
144
576
15 - 19
6
17
102
289
1734
20 - 24
9
22
198
484
4356
25 - 29
2
27
54
729
1458
30 - 34
1
32
32
1024
1024
f 30
fx 475
fx 29405
How to calculate the values found in the table above:
Class Interval
Chosen with a class size of5
F is the frequency of numbers
Found by looking at the ordereddata
X is the average of each class level
Ex. Class 10-14
X = 12
XF = 4 * 12 = 48
X2is the square of X
Ex. Class 10-14
X = 12
X2= 122= 144
FX2is the product of F times X2
10 14 7
2
FX is the product of F times X
Ex. Class 10-14
F = 4
Ex. Class 10-14
F = 4
X2= 144
F * X2= 4 * 144 = 576
Finding the Modal Class
The Modal Class is the class with the highest frequency (F) Class 20 - 24 has the highest frequency (F) of 9
Calculating standard deviation
There are two formulas for calculating standard deviation; the summations come from the table above
f 30
fx 475
fx 29405
Formula 1
Formula 2
fx2 fx2
SD = f f
9405 4752
SD =
30 30
SD= 313.515.52
SD = 63.6
SD = 7.9
fx2
fx
SD = n
n 1
4752
9405
SD = 30
30 1
9405 7520.8
SD =
29
SD = 64.9
SD = 8.0
Form 4
Introduction toresearch
Concept ofresearch
Types of Research - Descriptive, analytical, applied, fundamental (pure), quantitative, qualitative, conceptual, empirical
Descriptive - Research which deals with description a state that existspresently
Analytical - Use of facts or existing information and then analyzing them to make critical evaluations Applied - Aims to find a solution to an immediate problem facing a society or an organization Fundamental - Research which deals with generalizations or formation oftheory
Quantitative - Research which deals with the measurement of quantity or amount in numerical form
Qualitative - Deals with the quality of a phenomenon
Conceptual - The research which deals with abstract ideas or theory, so as to develop new concepts
Empirical - The research which relies on experience or observation without regarding system or theory
Objectives of Research - To be familiar with a phenomenon, to reveal accurate features of certain aspects of social life, test or approve hypotheses of casual relationships between phenomena
Importance of Research - Provides policy makers with accurate information about the subject matter, used to provide accurate solutions to social problems, used to direct social activities, providing reliable information to the data bank, members of society become well informed about their society
The benefits and problems of research - Benefits: Helps remove preconceived ideas in the researchers mind, creates a spirit of investigation, finds accurate solutions to problems, provides sources for future
research, used to improve production Problems: Takes a lot of time, research may be unsuccessful or useless, research is often only applicable to intellectuals
Why conducting field research is important - The method is systematic, objective, specific to a certain problem, encourages collection of original data
Problems that can be encountered during field research - Transport problems, climatic problems, language problems, instruments not being available, diseases, lack of human needs
Objectives of field research - Discovery of new knowledge, explanation of phenomena, description of a phenomenon, prediction of new principles or theories, theory development
How to conduct field research - Identify the problem, form a hypothesis, collect data, analyze data, data recording and presentation, testing the hypothesis, generalization
How to prepare yourself for field research - Understand the problem in well defined terms, know objectives of the research, awareness of geographical region, know types of data required and how to obtain them, know the sample of population to be studied, prepare tools for analysis, prepare a budget/work plan/time schedule
Important uses of research findings - Used to solve social problems, used by agricultural experts, preparing teaching materials and methods, improving governance, helps distribute social services, controlling diseases, to report data to the population, used by businessmen to develop business
Sampling Techniques - Method of getting samples from a population; random sampling, systematic sampling, stratified sampling
Quantitative Research - Based on the measurements of quantities or amounts of variables of a phenomenon
Research - Is the systematic collection of data used to understand a problem orphenomenon
ResearchTools-Methodsofdatacollectionincludingobservation,interviews,questionnaires
Non-probability sampling (Non-random sampling) - The elements chosen in the sample are not given an equal chance of being selected. (E.g. Handpicked sampling, snowball sampling, volunteer sampling)
Probability Sampling (Random Sampling) - States that each element in the population has an equal chance of being selected. (E.g. Simple random sampling, systematic sampling, stratified random sampling, cluster sampling)
Sampling - Is the process of selecting a small portion of the total population which will represent the entire population statistically
Hypothesis - Is a statement of speculation about the outcomes of research. It is the expected result of research by the researcher before going to the field to collect data
Field Research - Process of collection of data in a systematic manner with the aim of solving a problem
Stages of researchwork
Stages of conducting research - Identify problem, formulate hypothesis, labeling variable, establish a study design, data collection, analysis of information, report writing, conclusion
Research Techniques - Observation, measurement, interview, questionnaires, focus groups
Observation - Use of eyes to look at phenomena to record what is seen
Measurement - The way data is obtained by using equipment
Interview - Conduct a verbal interaction between an interviewer and interviewee
Questionnaire - Prepared questions to be answered by a respondent set by a researcher
Focus Group Discussion (FGD) - Involves intensive discussion about a particular issue done in a small group of people
Types of Hypothesis - Null, alternative
Null - One that is stated in negation, can be said to be true or false
Alternative - Indicates an actual expectation or relationship
Characteristics of a good hypothesis - States clearly the relationship between the variables, must provide sound rationale, consistent with commonly accepted notions, must be testable, must be related to empirical phenomenon, must be consistent with purpose of research, simple and concise
Purpose of hypotheses - Provides direction, ensures collection of evidence to answer research problem, sensitize the investigator to certain aspects of the situation, enables researcher to access information they have collected from respondents, permits researcher to understand problem with greater clarity and use it to find a solution, provides a framework for the ultimate conclusion of the research
Research Proposal - A systematic plan which plans what will be needed to accomplish the main objective of the research
Functions of a research proposal - Guideline to show how to proceed with a project, shows where the research should end, shows how the research will be evaluated in the future
Components of a research proposal - Title, problem and setting, hypothesis, literature review, work plan, budget chart, references
Qualities of a good research proposal - Should be clearly written, precise, reasonable length, worth time/money being used
Climate and naturalregions
World climatic types and theircharacteristics
(Not present in exams)
Natural regions of theworld
Trees of tropical rainforests and coniferous forests are evergreenTropical rain forests consist primarily of hard wood
Humanpopulation
Concepts of population
Age Structure of a Population - The distribution of ages of people in a society Birth Rate - The number of live births per year per 1000 people in the population Death Rate - The number of deaths per year per 1000 people in the population
Family Planning - Is the process of improving conditions of the family by ensuring an appropriate number of children and a proper spacing of time between one child and another
Growth Curve - The curve shape produced when the rate of growth of an organism or population is plotted on a graph
Infant Mortality Rate - Number of deaths of children below one year old per 1000 people in the population
Landlocked Countries - Countries without suitable harbours or access to oceans
Population - Is the number of people available in a given geographical area
Rural-Urban Migration - Movement of people, especially young people, from rural areas to towns and cities
Urbanization - Is the process of transformation in which a rural area develops into a town, from trade, modern buildings, population increase
Factors determining age structure in a population - Birth rate, death rate, infant mortality rate, migration, marriage status and rates
Explain the effects of rapid population growth on small scale agriculture - Causes deforestation, desertification, land conflict, food shortage, land degradation, water pollution, soil pollution
Effects of overpopulation on human and natural resources in East Africa - Not enough doctors/teachers for the large population, overexploitation of natural resources like water/land, lower standards of living, poor housing/social services
Characteristics of human populations - Population size, population density, population distribution, sex ration, age distribution, population growth rate, population change
Factors that influence population distribution - Physical factors like topography/climate/soil/vegetation, pests/diseases, war/government policies, economic factors like employment/industry
The aims of introducing family planning - To improve the living standards of the family, control population pressure, improve health of mothers and children, avoid STDs and unwanted pregnancy
The main problems facing family planning in Tanzania - Poverty, ignorance, cultural beliefs, religious beliefs, poor means of transport and communication to spread the message, lack of education, poor organization of groups spreading this message, laws such as allowing girls to marry at 15
Factors influencing rapid human population growth and distribution - Availability of food supplies, availability of clean/safe water supplies, pollution-free environment, availability of health services, availability of social services i.e. schools/markets, availability of infrastructure, availability of employment
Factors influencing population changes - Migration, death, birth, governmental policy
Settlements
Concept ofsettlement
Linear Settlement - Is a pattern of settlement where homes are along a road or railway system Nucleated Settlement - Is a pattern of settlement where homes are situated close to each other Scattered Settlement - Is a pattern of settlement where homes are situated far apart
Migration - Is the movement of people from one region to another
Growth ofsettlements
Settlement patterns are influenced by - Physical Factors: Climate/soil/topography, biological factors: pests/diseases/vegetation, Political Factors: War/policies/economics/culture
Explain the basic factors involved in setting up rural settlements - Availability of land and economic activities, climate, availability of water sources, vegetation, topography, pests/diseases, safety
Functions in an urban settlement - Administrative and economic centres, defensive functions, provision of higher education/health services, production centres, markets, entertainment, financial services
Negative impacts of rural-urban migration - Depopulation, failure of local economic activities, shortage of food production, breaking of family ties, environmental pollution in urban areas, unemployment, inadequate social services, increase in crime in urban areas as people struggle to survive
Main factors causing rural to urban migration - Absence of employment opportunities, land shortage, poor health services in rural areas, poor infrastructure, poor educational services, low income
Pure Nomadic Pastoralism - Pastoralists have no permanent residence and are in constant movement grazing from one place to another
Semi-nomadic Pastoralism - Farmers have permanent residence but during the dry season they travel long distances to look for pasture and water, have some level of cultivation to supplement income/food
The disadvantages of nomadic pastoralism in northern Kenya - Contributes to soil erosion from movement of herds, desertification from eating vegetation, does not allow farmers to settle, source of conflict between farmers and nomads over land use, animal diseases spread easily
Characteristics of nomadic pastoralism in East Africa - Not confined to a single area, animals are for subsistence purposes, poor health of animals, causes soil erosion/desertification, conflict between pastoralists and farmers, requires little capital
How to improve pastoralism in East Africa - Provision of education to farmers of modern ways of keeping livestock, adopt a range system to avoid desertification and soil erosion, provide health services to animals, provide storage facilities to farmers and livestock producers, improve transportation, have separate land for farmers and pastoralists
Factors which cause the different types of internal migration - More developed areas have more job opportunities, low agricultural productivity, poverty/hunger/underemployment, rapid increase in population, development of projects, government policies, war/violence, better social/health services
Environmental issues andmanagement
Concept ofenvironment
Ecosystem - Is a network of living organisms and non-living things interacting with each other
Features adopted by plants to survive in hot deserts - Long roots to penetrate to underground water, succulent leaves and stems for storage of extra water, waxy or needlelike leaves to prevent loss of water, seeds which are dormant for years until rainfall occurs
Cacti - Typical plants of a hot desert area, have long roots, thorny steps, needle shaped leaves, wax or hair
Importance ofenvironment
(Not present in exams)
Importance of the environment - Natural resources, human health, farming, tourism, beauty, biodiversity
Environmentalproblems
Environmental problems facing Tanzania - Environmental pollution from industry/agriculture/human activities, desertification, soil erosion, land degradation, deforestation from economic activities like charcoal production, loss of biodiversity
Examples of environmental hazards - Earthquakes, floods, bush fires, drought, volcanic eruption, tsunami, pollution, environmental degradation, desertification, deforestation
Environmental Degradation - The gradual or rapid decline of the quality of the environment required for animals or plants to live
Environmental Hazards - Are toxic materials or incidences which are harmful to humans or other animals, they can be caused by human activity or by natural occurrences
Acid Rain - Is rain which results from the mixture of moisture in the air with oxides of nitrogen and sulfur forming nitric acid, sulphuric acid, and carbonic acid
Effects of acid rain - Death of plants and animals, fills lakes/rivers/dams with acidic water, reduces quality of soil for agriculture, speeds up the rate of erosion of rocks, causes corrosion of infrastructure
Deforestation - The excessive massive cutting down of trees by humans for economic activity
Forestry - Is an economic activity which deals with the production of wood products and cutting of forests
Environmentalconservation
Measures taken to solve environmental problems in Tanzania - Environmental education in schools/colleges/universities, reforestation, protection of national forests, laws, restriction of harmful chemicals, restrictions on hunting
Ways to avoid environmental degradation in Central Tanzania - Afforestation and reafforestation, destocking, proper farming methods, alternative sources of fuel (non charcoal), encourage irrigation, diversify economic activities, increase education
Explain soil conservation measures in Kondoa District - Destocking, crop rotation, afforestation, reforestation, intercropping, filling gullies with brushwood
Causes of the loss of biodiversity - Human activities like agriculture or industry, expansion of grazing land into new habitats, urbanization, overexploitation of forests/oceans, fishing with dynamite, pollution
Biodiversity - Refers to the variety of life on earth in all its forms
Coniferous - They are cone-bearing seed plants with vascular tissue; all extant conifers are woody plants, the great majority being trees with just a few being shrubs
Deciduous - Consists of broad leaves and are found in temperate regions
Climate - Is the temperature, humidity, atmospheric pressure, wind, rainfall, and other meteorological elements in a given region over long periods of time
Clouds - Small particles of condensed water at the lower part of the atmosphere
Constant Volume Gas Thermometer - Measures temperature by the variation in volume/pressure of a gas
Desertification - Is the process of forming desert by increased heat on the Earths surface causing evaporation or by the destruction of forests
Dew - Is water in the form of droplets that appears on thin, exposed objects in the morning or evening
Doldrums - It is an area with low pressure in the tropics
Drought - A prolonged lack of moisture in an area as a result of a long period without rainfall
Fog - Is a cloud that is in contact with the ground
Front - The zone separating two air masses
Hail - Is a form of solid precipitation which consists of balls or irregular lumps of ice
Humidity - Is the amount of water vapor in the air
Hygrometers - Are instruments used for measuring relative humidity
Inter-Tropical Convergence Zone (ITCZ) - The zone between the maritime and continental air masses
Land Breezes - Occur at night due to the fact that land temperatures drop faster than water (because of different specific heat values), so it is cooler on the land than water
Macroclimate - Refers to the regional climate of a broad area
Maximum Temperature Thermometer - Used to measure the highest temperature reached in a day
Microclimate - A detailed small scale study of weather elements within a natural environment
Mist - Is a phenomenon of small droplets suspended in air
Polar Front - Where cold air from the Polar Regions meets warmer air from lower latitudes
Relative Humidity - Is the amount of water vapor that exists in a gaseous mixture of air and water vapor
Sea Breezes - During the day the breeze comes from the sea because the land is warmer and air travels from areas of high pressure to areas of low pressure
Sleet - A mixture of snow and rain
Trade Winds - Winds blowing from horse latitudes to the equatorial belts. Found in the tropics in the lower troposphere. Used in the past for trade and conquest by Europeans
Tropical Cyclone - A low pressure center with develops in low altitudes
Tsunami - A strong wave in the ocean caused by an earthquake or by a volcanic eruption
Weather - The state of the atmosphere measured by hot or cold, wet or dry, calm or storm, clear or cloudy Hurricanes and typhoons are tropical cyclones
Salinity of ocean water increases with an increased rate of evaporation of ocean waterWind blows from areas of high pressure to areas of low pressure
Weather andclimate
(Not present in exams)
Impact ofclimate
(Not present in exams)
Mapwork
Concept of amap
Choropleth Map - Is a thematic map in which areas are shaded or patterned in proportion to the measurement of the statistical variable being displayed on the map, such as population density or per- capita income
Atlas - Is a collection of maps; it is typically a map of the Earth or a region of the Earth
Components of amap
Contours - Lines that are drawn on the map joining different places with the same height above sea level
Isobar - Is a line connecting points of equal atmospheric pressure Isobeth - Is a line joining all place with equal depth in the ocean Isohel - Is a line of equal or constant solar radiation
Isohyet - Is a line joining points of equal precipitation on a map
Isoneph - Is a line indicating equal cloud cover
Time Zone - Is a region on Earth, more or less bounded by lines of longitude, that has a uniform, legally mandated standard time, usually referred to as the local time
Quantitative information aboutmaps
Essentials of a map - Key (legend or reference), scale, margin (frame), title, indication of north direction
Ways of showing topographical features on a map - Using contours, hill shading, layer colouring, form lines, hachure, benchmarks, spot height, trigonometrical stations (points)
Techniques of expressing scale of a map - Linear scale, statement (verbal) scale, representative fractional scale (RF scale)
Uses ofmaps
(Not present in study guide)
Humanactivities
Concept of humanactivities
(Not present in exams)
Form 2
Agriculture
Small scale agriculture
Small Scale Agriculture - Growing enough food for a family or small population, with little or no extra food for sale (ex subsistence farming)
Outline the main characteristics of small-scale agriculture - Simple tools are used, areas are small, low production, crops are starch based, poor transport, less use of chemicals to control diseases, family labour is used, local superstitious beliefs dominate among farmers
Effects of farming of on the environment - Erosion, destroys bacteria in the soil, overgrazing, deforestation, chemicals, artificial fertilizers tend to increase soil acidity, monoculture destroys fertility
Types of irrigation - Basin Irrigation, overhead irrigation, trickle irrigation, canal irrigation, tank irrigation, irrigation using lifting devices
Explain the tools or ways of empowering women in social and commercial activities - Giving education, loans, incorporating them into decision making, entrepreneurship training
Farming - Is the process of producing crops and keeping animals
Irrigation - Is the practice of ensuring that plants get enough water through artificial methods like the construction of dams, canals or tubes
Mixed Farming - The process of planting trees and growing crops in the same farm unit
Large scaleagriculture
Large Scale Agriculture - Growing of large amounts of crops to feed the population as well as for sale (ex. cash crops)
Disadvantages of large scale farming in Tanzania - Needs large capital investment to establish and maintain, dependent on crop prices, requires a lot of land, can lead to environmental degradation, contributes to migration to farming areas for employment
Causes of the failure to satisfy food demands in Africa - Poor technology, insufficient capital, climate failures, poor policy and implementation, pests/diseases, low level of education, rural-urban migration
Livestock keeping
Livestock Keeping - The practice of having animals such as goats or cows to provide milk, meat or economic value to an individual or family
The problems of beef cattle production in Tanzania - Insufficient capital, lack of adequate cold storage, transportation system, lack of markets, low quality of beef, diseases and pests, shortage of water and food for cattle, tradition of livestock keeping, ignorance of livestock keepers about proper methods of animal husbandry, no emphasis from government on beef cattle production
Beef cattle production can be improved through the following ways - Improvement of transportation and infrastructure, better education of farmers about animal husbandry, explore viability of new markets for beef cattle products, building of adequate storage facilities
Beef Cattle Production - Is the rearing of cattle for the purpose of producing products like meat or hides Destocking - Reducing the number of animals grazing an area of land compared to the lands capacity Overstocking - Is the act of grazing more animals on a piece of land than the land can handle Pastoralism - Is an economic activity whereby people live by grazing livestock on natural pastures Ranching - A system of keeping animals on a large piece of land
Water management for economicdevelopment
Importance ofwater
Economic importance of water - Encourage industrial development, improved family life, generation of HEP, agricultural development, development of transport, fishing industries, soil formation
Explain the need for and problems with irrigation in North Africa - Needs: Areas are semi-arid with low rainfall preventing crops from growing, nomadic groups there are not able to produce enough food for consumption and sale, population is increasing putting pressure on food supplies Problems: Lack of funds in Kenya, lack of modern technology, few irrigation engineers, nomads do not want to settle
Reasons East Africa has not developed an advanced fishing industry - Lack of capital or financial support, poor technology, ocean topography does not encourage fishing grounds, poor market for fish from East Africa, water pollution, poor means of transport, lack of storage facilities
Fishing Industry - Is an economic activity that deals with the production or harvesting of fish
River basindevelopment
The advantages of exploiting the Rufiji and Kagera river basins - Facilitates irrigation farming to produce food and cash crops, enables finish activities by construction of dams, harness water for hydroelectric power generation, source of clean water, provides employment
The disadvantages of exploiting the Rufiji and Kagera river basins - Environmental degradation or pollution, contribute to the loss of biodiversity, expensive infrastructure like dams and channels
Elaborate on the economic importance of forest resources in the Congo basin - Provides raw materials, provides foreign exchange, source of employment, brings economic diversification, develops transportation and communications in the region, can lead to industrial development
Landreclamation
Land Reclamation - The process of turning unproductive land to a useful state such as reclaiming desert land or creating land by filling the seabed
Steps that were taken in Netherlands to reclaim the land - Building of dams and dykes to retain water from the sea, draining of water using canals and pumps, planting reeds to allow water absorption by plants, burning of reeds to clear the area for cultivation, cultivation of reclaimed land
Aims of land reclamation - To control foods, to get more arable land, obtain land for settlement, improve navigation, get clean water
Sustainable use of waterresources
Benefits of establishing Tennessee Valley Authority in the USA - Increase in water supply for various uses, improvement in navigation, hydroelectric power, controlling flooding, creating employment, development of tourism, increase size of arable land, development of fishing industry
Waterpollution
Eutrophication - Excessive growth of algae in rivers and lakes owing to accumulation in the water of minerals such as nitrates which promote plant growth
Ways of reducing pollutants - Locate industry away from residential areas, recycle waste, efficient engines, efforts by government and other organizations to avoid environmental pollution, stronger policies, use of alternative energy resources, develop other safer activities
Sustainable use of forestresources
Types of forestryresources
(Not present in exams)
Importance of forestryresources
Importance of forests - Protect soil from degradation or erosion, habitat for animals, production of oxygen, providing building material, paper making, maintaining water sources, attract tourism, research studies
Afforestation - Is the planting of seeds or trees to make a forest on land which has not been a forest recently, or which has never been a forest
Agroforestry - Approach of using the interactive benefits from trees and shrubs with crops and livestock Reforestation - Is the reestablishment of a forest after removal, for example from a timber harvest Rejuvenation - The renewed activity of an ecological area such as a river or forest
Important areas of forest products, transport anduse
(Not present in exams)
Problems associated with forestry resourcesharvesting
Problems associated with the exploitation of forests - Poor capital, lack of valuable species of trees in tropical areas, dense tropical forests, poor transport, low technology, rapid population growth, challenges from environmentalists, coniferous trees face challenges from acidic rain in temperate areas
Problems facing the forestry industry in developing countries - Uncontrolled and unplanned cutting of trees, bad cultivation methods and burning of vegetation, wild animals destroy trees as they feed on them, depletion which is caused by higher demand for charcoal and firewood, spread of permanent agriculture, poachers and honey collectors, lack of transport infrastructure, developing countries do not set prices for wood products, many trees in tropical areas have no commercial value
Discuss the problems associated with exploitation of forest resources in developing countries like Malawi - Deforestation, drought, landslides, shortage of rainfall, soil erosion, loss of biodiversity
Sustainablemining
Types of mining
Mineral Ore - Is a type of rock that contains minerals with important elements including metals
(Not present in exams)
Types and distribution of mining regions in theworld
(Not present in exams)
Methods ofmining
Shaft Mining Method - Is the method of excavating a vertical tunnel from the top down, where there is initially no access to the bottom
Open Cast Mining (Open Pit Mining) - Is a method of extracting rock or minerals from the earth by their removal from an open pit
Contribution of mining to the economy ofTanzania
(Not present in exams)
Effects of the mining industry in theenvironment
Describe the effects of mining activities to the environment.- Pollution, soil degradation, land exhaustion, accelerates deforestation, disappearance of valuable plant species, greenhouse effects, spread of malaria due to standing water in mining pits
Factors affecting the exploitation of mineral resources - Availability and size of mineral deposits, quality of deposits, availability of capital to extract minerals, transportation system, availability of labour forces, methods used to exploit resources, market prices for minerals, availability of water supply to cool machinery and for washing minerals, government policy towards mining
Focal studies on oil and naturalgas
(Not present in exams)
Tourism
Concept oftourism
Ecotourism - Integrated approach that involves the carrying out of tourist activities with a minimum of negative impacts on the natural environment
Tourism - Is an economic activity which involves movements of people from their normal working places or homes to other places near or far away, for pleasure or recreation
Factors for the development and growth oftourism
Why East Africa is attractive to tourists - Presence of mountains and volcanoes, beaches and coral reefs, culture, art, historical sites, animals, national parks
Importance oftourism
Negative effects of tourism in East Africa - Environmental degradation, environmental pollution, spread of disease, cultural moral decay, spread of illegal drugs, increased government expenditure
Importance of ecotourism to the local community - Leads to empowerment of local economy, living standard is raised, locals gain respect of environment and its resources, preserve culture, builds relationship between visitors and local community, helps control diseases due to gaining of education, reduces water pollution, provide a market for local products (goods), stimulates development of transport, promotes environmental conservation awareness
Focal studies on the tourism industry
Explain the necessary conditional factors that contributed to the development of tourism industry in Switzerland - Availability of capital, good infrastructure and transport, scenery, good climatic conditions, availability of recreational activities, peace, located near other European nations
Manufacturingindustry
Concept and importance of manufacturingindustries
Manufacturing - Involves processing and changing the raw materials so as to make new products
Types of manufacturing industries
(Not present in exams)
Factors for location ofindustries
Outline the factors for the location of manufacturing industries - Availability of raw materials, markets, labour supply, power and energy resources, capital, transport and communication, good government support/policy, water supply
Factors limiting the development of dairy farming in East Africa - Poor capital, poor market, lack of storage facilities, poor breeds, lack of electricity and transport, poor technology, lack of skilled labour
Pollutants from manufacturingindustry
(Not present in exams)
Focal studies onmanufacturing
Importance of manufacturing industries to the world economy - Provides employment, foreign currency, promote development of technology, diversification of economy, leads to self sufficiency, improvement of economic activities like trade/tourism/agriculture, reduces expenses on imports, encourages improvement of social services, development of transportation and communication
Reasons Japan produces ships - Employs modern and advanced technology, possesses highly skilled employees/technicians, iron/steel industries exist in port towns, large and reliable market for ships, geographical nature of Japan, has little land for cultivation, economically developed
Factors for poor development of manufacturing industries in Tanzania - Poor capital, poor market, lack of skilled labour, lack of transportation, lack of technology and communication, lack of electricity
Reasons for the rapid expansion of industries in South Africa - Availability of capital, advanced technology, good transport and communication, ready market, availability of raw materials, presence of skilled and non-skilled labour
Explain the factors favouring dairy farming in Denmark - Development of science and technology, availability of capital, conducive climate, availability of pastures, skilled labour
Reasons for auto industry in Germany - Skilled technicians, advanced technology, availability of capital, ready market, availability of raw materials, power and energy resources, transport and communications
Sustainable use of power and energyresources
Define power andenergy
(Not present in exams)
Major sources of power & resources
Natural Resources - Naturally occurring substances that are considered valuable to human activities
Renewable Resource - Any natural resource that can be used without depleting its reserves
Hydroelectric Power - Use of water to create power through the use of turbines
Wind - Use of the wind to power turbines and create energy
Solar - Use of solar panels to get electricity from the Sun’s energy
Non-Renewable Resources - Resources whose reserves can be depleted
Petroleum - Oil used in cars, heavy machines or lubricants. Burned for energy and pollutes
Precious Stones - Gold, diamonds and other minerals mines for market or industrial uses
Ways to conserve natural resources - Avoid deforestation, make good laws, enforce environmental laws, modernize technology to avoid effects of mining or industry, protect water sources, education
Activities of man that affect natural resources - Agriculture, overgrazing, mining, cutting of trees for timber
Methods of acquiring or extracting power andenergy
(Not present in exams)
Importance and uses of power and energyresources
Preconditions for establishing hydroelectric power - Presence of a sufficient and constant supply of a large volume of water (i.e. lake or river), steep gradient or slope along the long profile of the river, presence of lakes along the river, availability of space to build dams and reservoirs, enough capital to invest and maintain the plant, presence of skilled technicians, modern technology, market for electricity
Advantages of hydroelectric power - Clean power, does not cause severe destruct of environment, dams help prevent flooding, provides employment, easy to maintain after initial installation, stimulates industrial development, developing nations can use hydroelectric power cheaply
Problems facing power and energyproduction
Problems associated with exploitation of energy resources - Pollution, low capital, low technology, lack of ready market, lack of skilled labour
Advantages and disadvantages of natural gas - Advantages: Efficient, cleaner than oil, easy to transport
Disadvantages: Explodes easily, causes air pollution, exhaustible (non-renewable)
Focal studies on wind and solar power in the USA and HEP and biogas inTanzania
Importance of natural gas to Tanzania - Improving standard of living, reducing cost of power, promotes environmental conservation, provide employment, brings in foreign currency, source of government revenue, stimulate exploitation of other energy resources like petroleum
Transport
Main types of transport
(Not present in exams)
Importance oftransport
(Not present in exams)
Problems facing the transportindustry
(Not present in exams)
2.9.0 Form 1 and 2 questions
Environmental lapse rate experiences temperature decreases by 0.6ºC per 100m
A football match started in Town X, 76ºE at 4:30 pm. What would be the time for a town at Greenwich Mean Time(GMT)?
Step 1: Find the difference in degrees of latitude
76º - 0º = 76º
Step 2: Find the difference in time. Divide the difference of degrees of latitude by 15
15º = 1 hour x = 76º
76
15
x 5 1 hours
15
Step 3: Change the fraction into minutes. Multiply the fraction by 60 since 1 hour is 60 minutes
1 * 60
15
x 4 min
Step 4: Find the difference. Moving west is subtraction, moving east is addition
The difference in time is 5 hours and 4 minutes. Since we must move west to reach the Prime Meridian, you need to subtract time
4:30pm - 5:04 = 11:26 am
If the time at Place X, 45º E is 10:00 am, what will be the time at Place Y, 45ºW?
Step 1: Find the difference in degrees of latitude
Since one place is east and one is west, the numbers are added, this is because they lie on opposite sides of the GMT
E + W
45º + 45º = 90º
Step 2: Find the difference in time. Divide the difference of degrees of latitude by 15
15º = 1 hour x = 90º
90
15
x = 6 hours
Step 3: Change the fraction into minutes In this problem there are no fractions to convert
Step 4: Find the difference, moving west is subtraction, moving east is addition 10:00pm - 6 hours = 4pm
Micheweni is at sea level and has a temperature of 32º C. What is the temperature of Karatu at 1500m above sealevel?
Step 1: Find the difference in altitude
1500m - 0m = 1500m
Step 2: Use temperature lapse rate to calculate temperature
Temperature Lapse Rate: 100m = 0.6º C
x is the difference in altitude from step 1
x = 1500m
Step 3: Multiply the left sides together and right sides together of each equation
Equation 1: x = 1500m
Equation 2: 100m = 0.6º C
Final Equation:
100x = 0.6º C * 1500m
Step 4: Isolate x on the left side of the equation by dividing by 100
100x 0.6º C *1500m
x 0.6º C *1500m
100m
x = 9ºC
Step 5: Take x and subtract from the temperature of Micheweni, you subtract because Karatu has a higheraltitude
32ºC - 9ºC = 23ºC
What is the longitude of Morogoro if its local time is 10:00 pm, whereas the longitude of Accra in Ghana is 0º and the local time is7:00pm?
Step 1: Calculate the difference in time
10:00pm - 7:00pm = 3 hours
Step 2: Find the difference in degree. Multiply the
x 15º * 3 hours
x = 45º
number of hours by 15
15º = 1 hour x = 3 hours
Since Morogoro is East of Ghana, the longitude of Morogoro is 45º E
Form 3
Structure of theearth
The earth’s crust, mantle andcore
Order of Layers -
Lithosphere - Contains thecrust
Mohorovic Discontinuity - Boundary between crust andmantle
Mantle - Contains the Asthenosphere
Gutenberg Discontinuity - Layer of rocks between mantle andcore
Core (Barysphere) - Contains inner and outercore
Sial and sima are the rocks that make up the outer crust of theEarth
Water Table - Is the level at which the groundwater pressure is equal to atmospheric pressure and is the upper limit of the saturation of water in a saturated rock
Asthenosphere - Is the region of the upper mantle of the Earth and balances the movements of Earths materials
Barysphere (Core) - Scientific name for the core, made up of iron and nickel
Conrad Discontinuity - Is the border between the upper continental crust and the lower one (sial and sima)
Core - Interior layer of the earth which is subjected to great heat and pressure
Gutenberg Discontinuity - The layer of rocks which separates the mantle from the core Hydrosphere - Is the combined mass of water found on, under, and over the surface of planet Lithosphere - The hardest part of the Earth’s crust (Litho means rock), geographical name of the crust Mohorovic Discontinuity - Is the boundary between the Earth's crust and themantle
Sial - Part of the Earth forming the upper part of the crust or continental blocks
Sima - The lower part of the Earth’s crust
Types of rocks of the earth’scrust
Conglomerate - Is a rock consisting of finer-grained materials that have become cemented together
Igneous Rock - Is formed through the cooling and solidification of magma or lava
Metamorphic Rocks - Are formed by the transformation of a rock by pressure and heat inside the Earth
Sedimentary Rocks - They are usually found in layers, important minerals can be found there, some are deposited by wind; they can be formed organically, chemically, or mechanically
Shale - A sedimentary rock composed of rounded gravel-sized particles
Examples of metamorphic rocks - Granite, slate, marble and gneiss
How sedimentary rock is formed - Formed by cementation and compaction of sediments arranged in layers by deposition
Features of sedimentary rocks - Usually found in layers, contain important minerals, can be deposited by water or wind, are formed organically/mechanically/chemically
Economic importance of rocks - Provide building material, used for industry, formation of soil, storage of underground water, provides fuel (coal), manufacturing of cement, salt extraction, decoration in houses
Economic significance of sedimentary rocks - Contain building material, used as decorative material, provide energy (coal), production of cement, formation of features in karst regions
Quartz is a compound element of silicon and oxygenGranite and basalt are examples of igneous rocksMarble is metamorphized limestone
The three main groups of rocks on the surface of the earth are igneous sedimentary and metamorphic and are classified according to how they were formed
Igneous rocks are formed when molten rocks from the mantle cool and solidifyClay is classified as an impermeable rock
Simplified geological time scale
Order of time periods of the geological time scale: Oldest
Paleozoic - Primaryperiod
Mesozoic - Middleperiod
Cenozoic - Modernperiod
Youngest
Cenozoic Era - The most recent of the three classic geological eras and covers the period from 65.5 million years ago to the present following the Mesoic Era
Geological Time Scale - Is a chart which is used to date rocks to understand how landforms were created
Forces that affect theearth
Forces causing earth movements 3.2.2 Internalforces
Internal forces operating in the Earth - Diastrophic forces
Radial/vertical and lateral/horizontalmovement
Features caused by faulting - Formation of rift valleys (graben), horsts, plateaus, basins, block mountains, fault scarps, tilt block landscape, changes drainage and causing of earthquakes, occurrence of springs River Valley (Graben) - Is a depressed block of land bordered by parallel faults. A graben is the result
of a block of land being downthrown producing a valley with a distinct scarp on each side. Graben often occur side-by-side with horsts
Horsts - Is the raised fault block bounded by normal faults or graben. A horst is formed from extension of the Earth's crust. The raised block is a portion of the crust that generally remains stationary or is uplifted while the land has dropped on either side
Plateau - An extensive elevated region with a gentle undulating surface with a uniform summit level
Spring - Is a natural occurrence where water flows to the surface of the earth from below the surface. Thus it is where the aquifer surface meets the ground surface. Forms from a dyke cutting across a layer of permeable rock
Aquifer - A natural outflow of water from the surface rock
Artesian Aquifer - Is a confined aquifer containing groundwater that will flow upward through a well, called an artesian well, without the need for pumping
Types of earth movements (caused by either compressional or tensional forces) - Vertical movements, lateral movements (orogeneses)
Types of folds - Symmetrical, asymmetrical, over fold
Symmetrical Fold - A fold produced with limbs of similar nature
Asymmetrical Fold - A fold where one limb is steeper than the other, they are not similar
Overfold - Fold formed when compressional forces push one limb of an asymmetrical fold over another
Types of faults - Normal faults, reverse faults, tear (transformation, shear) fault
Normal Faults - Produced by tensional forces
Reverse Faults - Caused by compressional forces
Tear Fault - A vertical fracture produced when two blocks slide against one another
Examples of fold mountains - Rocky mountains, Appalachian mountains, Alps, Andes, Atlas, Himalayas
How a graben (rift valley) forms - Is formed when faults between two rocks sink down due to either compressional or tensional forces
Anticline - Is a fold that is convex up and has its oldest beds at its core
Block Mountains - Are formed when large areas of bedrock are widely broken up by faults creating large vertical displacements of continental crust
Compression Forces - Causes a wrinkling of the Earth’s surface due to forces pushing towards each other Exfoliation Joints - Are surface-parallel fracture systems in rock often leading to erosion of concentric slabs Fault - Is a fracture in the crust due to stress or strain associated with rock displacement
Faulting - Is the fracturing of the crust to form faults
Folding - Is when one or a stack of originally flat and planar surfaces are bent or curved
Lateral Forces - When two forces act away from each other laterally
Joint - Is a crack in the rock due to stress but is not associated with rock displacement
Orogeny - Refers to forces and events leading to a severe structural deformation of the earth's crust due to the engagement of tectonic plates
Range - Chain of mountains bordered by highlands or separated from other mountains by passes or valleys
Set of fault types - Normal fault, reverse fault, tear (symmetrical) fault
Syncline - Is a downward-curving fold, with layers that dip toward the centre of the structure Tectonic Plates - Is a scientific theory which describes the large scale motions of Earth's lithosphere The difference between faults and joints is that joints have no associated displacement
Fold mountains are caused by compressional forces
Vulcanicity
Features with volcanicity - Caldera, craters, dyke, laccoliths, plug dome, solfatara, phacolith, lopolith
Caldera - A feature formed as a result of a violent volcanic eruption and is shaped like a large basin or depression on the top of a volcano
Dyke - A vertical feature formed out of the solidification of magma within the Earths crust, forms across a bedding plane of bedrock
Laccolith - Is a sheet igneous intrusion that has been injected between two layers of sedimentary rock Lopolith - Is a large igneous intrusion which is shaped like a lens with a depressed central region Phacolith - Lens-shaped strip of igneous rock formed if magma solidifies along anticlines or synclines Solfatara (Fumarole) - Is an opening in the Earth’s crust near volcanoes which emit steam and gasses
Features of intrusive vulcanicity - Dyke, sill, laccolith, Lopolith, Phacolith, batholith
Sill - Is a flat sheet intrusion that has intruded between older layers of sedimentary rock, beds of volcanic lava, forms along the bedding planes of bedrock
Batholith - A large mass of solidified rock formed when magma cools in the heart of mountain ranges
Major extrusive volcanic features - Caldera, crater, shield volcano, crater, ash and cinder cone (scoria cone), composite cone (strato-volcano), volcanic plug (plug dome volcano), acid lava cone
Crater - A depression formed on the summit of the cone after the plug has been blown off
Shield Volcano - A broad domed lava cone with gently sloping sides
Volcanic Plug - The solidified volcanic feature within the vent that prevents an eruption Ash and Cinder Cone - A cone shaped accumulation of rock fragments around a vent Composite Cone - A large cone with alternate layers of fragments from ash or lava
Acid Lava Cone - A dome shaped volcano with convex slopes formed when acidic lava solidifies around a vent
Minor extrusive volcanic features - Solfatara, fumerole, hot springs, geysers
Hot Springs - Spring caused by the emergence of heated groundwater from the Earth’s crust
Geyser - Is a spring with an intermittent discharge of water ejected violently and accompanied by a vapour phase (steam)
Types of volcanoes - Dormant, extinct, active
Dormant - A volcano which has stopped erupting but can still erupt at any time Extinct - A volcano which has stopped erupting and will not erupt again Active - A volcano with erupts frequently
Lava - Is molten rock expelled by a volcano during an eruption, is the name of magma on the surface Magma - Is a mixture of molten rock and solids that is found beneath the surface of the Earth Volcanic Eruption - The forceful emission of magma from the core of the Earth through a vent
Volcano - Is an opening, or rupture, in a planet's surface or crust, which allows hot magma, ash and gases to escape from below the surface
Volcanism - Refers to the range of processes by which molten material and gasses are either intruded into the Earth’s surface or extruded from the Earth’s surface
Characteristics of a shield volcano - Forms from fluid lava which flows to cover a large surface area, formed by basaltic lava, lava flow is slow, not very tall but occupies a large surface area, crater is small due to slow rate oferuption
A volcanic eruption is most likely to be violent if the lava reaches the surface through a fissure due to highpressure inside thevolcano
Earthquakes
Causes and effects of earthquakes - Causes: Tectonic forces (diastrophic forces), faulting of lithosphere, volcanism, mass movements, falling of meteorites, mans activities (e.g. quarrying, explosives), movements of large amounts of animals Effects: Death, destruction of property, formation of joints in the rocks, landslides, collapse of buildings, tsunamis, fires
Crest - The upper part of a wave
Earthquake - The sudden movement of the Earths crust along faulted and volcanic areas when tectonic plates collide with each other
Epicenter - Is the point on the Earth's surface that is directly above the focus
Focus - Is the point where an earthquake originates
Magnitude - Refers to the total amount of energy released by an earthquake
Mercalli Intensity Scale - Is a scale used for measuring the intensity of an earthquake Richter Scale - Measures the amount of energy released by an earthquake Seismography - Measures the intensity of an earthquake
Seismology - The study of the Earths movements such as earthquakes or tremors
Trough - The bottom part of a wave
Externalforces
External forces operating on the Earth’s surface - Exogenic forces, denudational forces
Mass wasting
Mass Wasting - Is the geomorphic process by which soil, regolith and rock move downslope under the force of gravity. Is caused by the process of granular disintegration, tips electric polls and fences
Eluviation - The process of the removal of materials from geological or soil horizons
Denudation - The process of rock disintegration by means of erosion, weathering, or mass wasting
Forms of slow mass wasting - Soil creep, talus (scree) creep, solifluction (sludging)
Soil Creep - Slow movement of soil particles which can be recognized by bending of trees and fences
Talus Creep - Very slow movement of waste rock of all sizes down a slope
Sludging - The gravitational flow of soil mixed with gravel saturated with water down a slope
Forms of rapid mass wasting - Earth flow, mudflow, avalanches, landslides, slumping, rockslide, debris slide, rock fall
Earth Flow - A downslope viscous flow of fine grained materials that have been saturated with water, and moves under the pull of gravity
Mudflow - The movement of large volumes of materials which are supersaturated with water as mud Avalanches - The sudden and catastrophic movement of materials down a slope with snow Landslides - Movements of materials which slip rapidly down a slope
Factors affecting mass wasting - Gradient(slope), climate, vegetation, nature of material and extent of saturation, endogenic forces (tectonic forces), human beings
Effects of mass wasting in our daily life - Death, loss of property, soil erosion, formation of fertile soil, creation of lakes, creation of tourist attractions, land degradation
Weathering
Weathering - The destruction of rocks by climatic conditions such as rain or temperature change
Types of weathering - Mechanical, chemical, biological (biotic)
Forms of mechanical weathering - Exfoliation, granular disintegration, block disintegration, shattering
Exfoliation - The peeling off of the outer layer of the rock due to high temperatures Granular Disintegration - The breaking up of rocks which consist of different minerals Block Disintegration - Takes place when a homogeneous rock breaks into blocks due to
temperature, common in rocks that are well jointed
Frost Shattering - Freezing and thawing causes the rocks to expand and contract until they break
Types of chemical weathering - Oxidation, carbonation, hydration, hydrolysis, solution
Oxidation - The process where minerals are oxidized when they combine with oxygen and water
Carbonation - Takes place when a weak acid in rainwater reacts with rocks composed of calcium carbonate such as limestone
Hydration - When certain minerals absorb water and swell causing fracturing of the rock
Solution - The process where some soluble minerals dissolve e.g. rock salt
Factors affecting the rate weathering - Nature of the rocks, climate, organisms, relief(slope)
Nature of the rocks - Mineral composition, rock structure, colour
Climate - Climatic variations increase or decrease the rate that rocks weather Organisms - Plants and animals can break apart rocks chemically or mechanically Relief - Steeper slopes can cause rocks to break apart
Chemical weathering is the result of organic acid and weak carbonic acidChemical weathering is most effective when it is hot and wet
Tors - Rock outcrops formed by weathering which is usually found on near the summit of a hill, formed when joints develop in rocks
Wind Attrition - The process by which rock particles rub or collide against each other when they are carried along with the wind
Wind Deflation - The process by which the wind blows away loose rock waste and in doing so, lowers the desert surface producing depressions
Wind Abrasion - The process by which small particles of rock are hurled by the wind against rock surfaces to blast away features
Erosion and deposition by water, ice, wind and wave action Water
Types of deserts - Sandy, rocky (erg), badlands, mountainous
Erg - A stony desert
Depositional features due to water action in deserts - Alluvial fans, alluvial cones, bajadas (bahada), peripediment, playas (sebkhas/chotts) and Salinas(salars)
Alluvial Fans - Fan-shaped features formed when large quantities of sediments are deposited at the foot of steep slopes
Alluvial cones - Look like alluvial fans but consist of coarser material
Bajadas - Continuous gently sloping features with an undulating surface formed when alluvial fans/cones coalesce during the deposition of more sediment at the foot of a steep slope
Playas/Salinas - Are temporary salt lakes
Peripediment - A gentle slope formed when alluvial deposits overlie the edge of the pediment surrounding the playa
Erosional features due to water action in deserts - Rills, gullies, wadis (chebka), pediment, pediplains, inselbergs, mesas, buttes, dry river valleys
Rills - Small, shallow grooves formed due to erosion by surface runoff
Gullies - Deep, steep troughs produced when erosion in rills becomes larger
Wadis - Steep-sided, deep and flat floored valleys formed due to severe erosion by water in the desert
Pediment - Gently sloping platform formed when the edges of the desert and semi-desert highlands get pushed back by erosion and weathering
Pediplains - Multi-concave features resulting from the coalescing of several adjacent pediments
Mesas - Extensive flat-topped residual tablelands with resistant rock on the top
Buttes - Small but prominent residual flat-topped hills capped with resistant rock which remain after denudation of a plateau in arid areas
Dry River Valleys - River valleys which remain dry after streams of water dry during the dry season
Surface features of a karst region (limestone surface features) - Scarps, hills and mountains, grikes (grykes), clints, swallow holes (sink holes or ponor), doline, uvala, polje, gorge, terra rosa
Terra Rosa - A red clay which is found in floor of a polje
Scarps/Hills/Mountains - Formed when there are hard rocks which have not been eroded away that remain standing as residual features
Grikes - Gullies formed when water erodes the cracks on the surface before going underground
Clints - Ridges or blocks in limestone rock separating grikes in a karst region
Sinkhole (Swallow Hole) - A vertical hole produced when the joints are enlarged by water percolating into the rock
Doline - Is a large depression produced when several swallow holes coalesce (join together)
Uvala - Is a large depression formed when Dolines coalesce
Polje - A very large depression formed when several uvalas collapse
Gorge - Steep sided trough lined by steep rocky cliffs which form when the roof of the cavern collapses
Karst - A well developed surface of a limestone region where the rocks are well jointed
Limestone - A soluble rock with jointed structures resembling a wall
Underground features of a limestone area (caves) - Caverns, stalactites, stalagmites, underground river, natural pillar, anthodites, resurgent river
Caverns - Underground chambers formed due to the solution of limestone rock underground Stalactite - Long needle like calcite rock that hangs downward from the roof of a limestone cave Stalagmite - Is a type of structure found on the floor of a limestone cave due to the dripping of
mineralized solutions and the deposition of calcium carbonate
Underground River - The river formed when water sinks underground through sinkholes and joints
Natural Pillar - A natural column formed when a stalactite and stalagmite join together or when a stalagmite reaches the roof
Anthodites - Delicate flower-like formations which are formed when calcite is deposited on the roof of caverns
Resurgent River - An underground river that reappears on the surface somewhere
The amount of water that sinks into the ground from the surface depends on the underlying geological structure
Erosional features in the upper section of a river (young stage, river torrent, or river mountain) -
V-shaped valley, interlocking spurs, river capture, waterfalls, canyons(gorge), rapids, pot holes, plunge pool, boulders
V-shaped Valley - A valley with a strong gradient which is formed due to the river’s high velocity
Interlocking Spur - Is a natural geographical feature which occurs in a river's upper course, where vertical erosion is the dominant force in determining the river's course
River Capture - Process where a stronger river captures a weaker river when the stronger river erodes its valley both vertically and headword at a faster rate and flows at a lower level than the weak river
Waterfalls - Sudden downpours of water along a river due to the sudden drop of slope in the riverbed
Canyon - A deep ravine cut between cliffs like mesas, buttes, or plateaus by a river in a desert climate
Rapids - The sudden descent of the stream of water without a waterfall, the slope is not steep enough Pot Holes - Shallow depressions cut by pebbles as they are carried by swirling water on the riverbed Plunge Pool - A large deep depression that develops at the base of waterfalls due to abrasion by
pebbles carried in the river
Boulders - Large rocks broken up by river erosion that are too heavy to be taken downstream
Features resulting from river capture - Elbow, pirate river, wind gap, misfit river
Elbow - The bend produced where the river has been diverted
Misfit River - Stream which lost headwaters due to its volume being capture by another river
Wind Gap - The valley behind the misfit river in between the misfit river and the elbow
Pirate River - The river which takes volume from the misfit river and is rejuvenated in the process
Features in the lower section (old stage, or flood plain of the river) of a river (depositional features) -
Flood plain, natural levees, ox-bow lakes (Cut-offs), deferred tributary, deltas, estuaries
Flood Plain - A gently sloping area produced as a result of deposition of alluvium (silt and sand)
Levee - Embankments produced as the result of deposition of sediments along the bank of the river in the flood plain. Also created by humans to prevent flooding
Ox-bow Lakes - Cut-off meanders formed as the river cuts through the necks of the loops or well established river bends
Deferred Tributary - A tributary in the lower course of a river that has been forced to flow alongside the main valley before joining the river
Deltas-Lowlying swampyplainformedastheresultofaccumulationofalluviumatthe mouthofariver
Estuary-Rivervalleythathasbeendrownedbya riseinsealevel orthefallofthelandalong thecoast
Basin lakes of Africa - Victoria and Chad
Types of river rejuvenation - Dynamic rejuvenation, static rejuvenation
Dynamic Rejuvenation - Rejuvenation brought about by either sea level change or land level change
Static Rejuvenation - Is the type of rejuvenation caused by the increase in the river volume due to heavy rainfall, melting of ice or river capture
Features due to river rejuvenation - Knick point (rejuvenation head), paired terraces, incised meanders Knick Point - Break of the slope in the long profile of the river valley where the riverbed drops sharply Paired Terraces - Steps or benches on either side of a river valley formed as a result of undercutting of
the river due to renewed erosion
Incised meanders - Steep sided curved bends of the river valley produced as a result of the undercutting of the riverbed by the river along the meander
Rejuvenation - The renewed activity of an ecological area such as a river or forest
Types of drainage patterns - Dendritic pattern, trellised pattern (rectilinear pattern, rectangular pattern, radial pattern, annular pattern, centripetal pattern, and parallel drainage pattern
Dendritic Pattern - Looks like a tree trunk with its branches as veins, possessing many tributaries
Trellised pattern - Develops in areas with alternating hard and soft rock, the tributaries join the main river valley at almost right angles
Rectangular Pattern - Its tributaries join the main river at a right angle
Radial Pattern - The drainage pattern where streams flow outwards down flanks or slopes of a dome or cone such as a volcano e.g. Kilimanjaro
Annular Pattern - A series of streams flowing in a spiral way forming concentric circles Centripetal Pattern - Streams flowing from all directions converge at the center in the basin Parallel Drainage Pattern - A series of streams running parallel to one another
Types of drainage systems - Accordant drainage system, discordant drainage system
Accordant Drainage System - The normal drainage system of a river, the water flows in accordance to rock structure and slope
Discordant Drainage System - Does not flow in accordance with rock structure or slope
Accordant drainage systems are seen by the following drainage patterns - Radial, trellised, rectangular, centripetal drainage patterns
Discordant drainage systems - Antecedent, superimposed, anteposition
Antecedent - A river maintains its course by eroding vertically up the land due to having enough velocity to go up the slope
Superimposed - The opposite of an antecedent, the river maintains its course into a newly exposed rock layer without following the structure of the rock
Anteposition - Develops as a result of the combination of antecedence and superimposition
Alluvium - Loose soil or sediments, eroded, deposited, and reshaped by water on Earth’s surface
Deposition - The laying down of rock particles on the surface
Importance of rivers - Water supply, transport, hydroelectric power, sources of materials like sand/diamonds, fishing grounds, tourism, irrigation
Causes of river rejuvenation - A fall in the sea level (eustatic change), land uplift and subsidence (isostatic change), increase in the river volume (discharge)
Conditions necessary for the growth of coral polyps:
Warm waters with temperatures between 20-30 degrees Celsius
Clear salty water, hence they do not occur at rivermouths
Sunlight that penetrates to a depth of about50m
Plentiful supply of plant food andoxygen
Types of coral reefs - Fringing reef, barrier reef, atoll
Fringing Reef - A reef attached to the coast with a shallow lagoon separating it from the mainland
Barrier Reef - Similar to a fringing reef but the barrier reef is farther away from the coast and is separated from the mainland by a larger deeper lagoon
Atoll - Circular or elliptical shaped coral reef enclosing a lagoon found in mid oceans
Features of an ocean floor - Continental shelf, continental slope, trench, plateau, basin, plain, deeps
Ocean Ridge - Is an underwater mountain range, typically having a valley known as a rift running along its spine, formed by plate tectonics
The continental shelfis the best place for commercial fishing
Attrition - Collision of loads with each other and broken down in a river
Cross profile of a river - Distance between one side of a river and the next Dendritic Drainage - A drainage pattern which looks like a tree with its branches Drainage Pattern - Is the plan or layout of the river with its tributaries Formation of a river delta - First corrasion, then transport, thendeposition
Hydraulic Action - Wearing away of the sides and bottom of a river’s channel by the load carried by a river
Long profile of a river - Stretch of the river from its source to its mouth
Meander - Is the bend in a river as it courses downriver
Potholes - Is a type of disruption in the surface of a roadway where a portion of the road material has broken away, leaving a hole
River Rejuvenation - Is the renewal of the erosive activity of a river in its valley
River Valley - A section of a river where erosion is pronounced and is characterized by a V-shaped valley The source of a river is the catchment area
The erosive power of a river depends mainly upon its volume and speedRiver water can flow in the following two ways: Laminar and turbulent
Waves
Features due to wave deposition - Spit, tombolo, sand bar, mudflats, beaches, berms, cusps
Spit - A low narrow ridge of sand attached to the land at one end with the other side ending in the sea
Tombolo - Is a deposition landform in which an island is attached to the mainland by a narrow piece of land such as a spit or bar
Mudflat - Are coastal wetlands that form when mud is deposited by tides or rivers. They are found in sheltered areas such as bays, bayous, lagoons, and estuaries
Beach - Lies between the high and low water levels (tides), formed by deposition of sand along water Berm - A narrow ridge or shelf with a steep front which is found on the upper part of some beaches Cusps - A series of small, horn-shapes projections separated by shallow indentations that face
seawards giving the beach a curved appearance
Sand Bar - A ridge of material which lies parallel or almost parallel to the coast or across the estuary or bay between two headlands
Features due to wave erosion - Cliffs, wave-cut platforms, bays, caves, blowhole (gloup), arch, geo, stack, stump, headland
Cliff - Is a high perpendicular or steep rock face along a sea coast produced by waves below
Wave-Cut Platform - A plateau like structure produced by continual undercutting of a cliff by waves
Headland - Is a high promontory with a steep face which projects into the sea or a lake when less resistant rocks are eroded away
Bays - A curved indentation of the sea into the land which is formed by the erosion of less resistant rock
Cave - Is a tunnel-like opening at the base of a cliff face that forms where there is a weakness in the rocks (joint or fault) through constant wave erosion by abrasion and hydraulic action
Arch - Is a roof-like structure formed as a result of a headland being eroded right through from one cave to the other side of the headland
Stack - Is an isolated mass of rock near a coastline detached from the mainland by wave erosion which caused the collapse of an arch
Stump - Is an isolated mass of rock which was formed as a result of a stack being considerably eroded
Blowhole - Is a hollow structure nearly vertical on the land formed when erosion occurs along a vertical joint which passes from the land surface to the cave roof
Geo - A long narrow inlet of the sea, penetrating cliffs that have been formed as the result of the collapse of the roof joining a cave and blowhole
Shore - The land between the high tidal water level and the low tidal water levels
Shoreline - The line where the shore and sea meet
Classification of Coasts - Submergent coasts, emergent coasts, stable coasts, compound coasts Submergent Coasts - Result from the rise of the sea level or submergence of land Emergent Coasts - Result from the fall in sea level or uplift ofland
Stable Coasts - Coasts formed where there is little change
Compound Coasts - Produced from the mixture of emergences and submergences
Types of submerged upland coasts - Ria coasts, fiord coast, dalmation coasts (longitudinal coasts)
Ria Coast - Formed when the highland area with river valleys is submerged and the lower parts of its river valleys become flooded by water from the sea
Fiord Coast - Formed when glaciated U-shaped valleys are flooded after the submergence of the former coastal highland area
Dalmation Coast - Form where a mountainous area which lies parallel to the coast is submerged, forms valleys called sounds
Lakes
Classification of Lakes - Created by diastrophic movements, volcanic activity, erosion, deposition, man
Lakes caused by diastrophic movements - Rift valley lakes, down-warped lakes
Rift Valley Lakes - Formed when water occupies rift valleys formed as a result of faulting
Down-Warped Lakes - Formed when water occupies basin-like depressions
Lakes due to volcanic activity - Crater and caldera lakes, lava dammed lakes
Crater and Caldera Lakes - Formed when water occupies a crater or caldera
Lava Dammed - Formed when a river is blocked by lava that erupts and runs across the river
Lakes due to erosion - Glacial lakes, trough lakes, rock basin lakes
Glacial Lakes - Tarn lakes formed when water fills land occupied by cirques
Trough Lakes - Lakes formed when water occupies hollows on the floor of U-shaped valleys
Rock Basin Lakes - Formed when water occupies the depressions formed on the rock surface
Lakes due to deposition - Glacial depositional lakes, moraine dammed lakes, kettle lakes, ox-bow lakes, delta lake, flood plain lakes, marine deposition, lucastrine
Lucastrine - A delta which is found in a lake
Lakes which occur as a result of deposition - Playa, Ox-bow, Delta, Lagoon
Playa - Is a desert basin with no outlet which periodically fills with water to form a temporary lake
Ox-bow Lake - Is a waterhole that forms at the lower side of the river, where the river develops meanders while deposition is taking place
Delta - A broad tidal channel where a river enters the sea
Lagoon - Is a body of shallow sea water separated from the sea by some form of barrier Lake - Is a hollow or depression on the Earth’s surface where water has accumulated Manmade Lakes - Are formed as a result of the construction of a dam across a river
Ice
Sapping - The breaking of rocks by the alternation between thawing and freezing of water at the bottom of cracks in glaciated land
Erosional features formed in a glaciated highland - Truncated spur, U-shaped valley, pyramidal peak, arête, cirques (corrie/cwm), hanging valley, fjord, ribbon lake
Pyramidal Peak - Mountaintop that has been carved by ice during glaciation and frost weathering
Cirque (Corries) - Circular depressions which are formed by glaciations in the highlands
U-Shaped Valley - A steep-sided, flat bottom, wide valley which contains features produced by both glacial erosion and deposition
Arête - A steep ridge separating two cirques which is formed by cutting back of the walls of cirques Truncated Spur - Spurs whose ends have been cut off due to erosion as ice moves down the valley Hanging Valley - Is the tributary valley of the U-shaped valley which hangs above the floor of a U-
shaped valley separated by an almost vertical slope. If there is a river a waterfall will form
Fjord (Fiord) - Is a submerged glaciated U-shaped valley formed when the glacier has eroded its path by undercutting and been plunged into the sea
Ribbon Lakes - Lake that occupies an elongated trough excavated by ice in a U-shaped valley
Tarn Lake - Is a mountain lake or pool, formed in a cirque excavated by a glacier
Erosional features formed in a glaciated lowland - Eroded plain, crag and tail, roche mountonée
Eroded Plain - Is a rounded topography with a large area of bare rock scratched by boulders embedded in the base of the glacier
Crag and Tail - Is a resistant mass of rock standing in the path of a moving glacier
Roche Mountonée - Outcrop of resistant rock smoothed by a glacier into a gentle slope
Depositional features of a glaciated lowland - Till plain (boulder clay plain), drumlin, erratics, kames, eskers, kettles, moraines, outwash plains, kame-terrace
Till Plain - A long plain made of clay and boulders deposited by ice sheets and glaciers over a surface which contains features like erratics, drumlins, kames, eskers and kettles
Kettles - Are the depressions formed after the melting of the ice block enclosed within the till
Erratics - Are large boulders deposited by a glacier or ice sheets as they melt Drumlin - Elongated egg-shaped hills made of boulder-clay which occur in groups Moraines - Refer to the boulder clay deposits laid down in the lowlands to form ridges
Lateral Moraine - Lines of glacial deposits along the sides of valleys
Medial Moraine - Consist of rock fragments deposited in the middle of the valley which marks the point where two glaciers met
Terminal Moraine - Refers to the ridge like feature found at the end of a glacier
Recessional Moraines - Series of parallel terminal moraines that mark the retreat of glaciers
Esker - Is a long winding ridge of stratified sand and gravel
Kame - A feature of an irregular undulating mound of bedded sands and gravel
Kame-terrace - Is a discontinuous ridge along the valley side formed by deposition of sands in narrow lakes between a glacier and the adjacent rock wall
Outwash Plain - Is a wide gently sloping plain formed as the result of deposition of material by melt- water from the glacier
Wind
Erosional features due to wind in deserts - Rock pedestals, zeugen, yardangs, blowouts (deflation hollows/pans), inselbergs, desert pavements, ventifacts (draikanter)
Rock Pedestals - Tower like structures composed of alternate bands of soft and hard rock formed due to wind abrasion in the desert
Zeugen - Ridges consisting of alternate layers of hard and soft rock formed in areas where rock layers lie horizontally and are characterized by joints
Yardangs - Are the ridges consisting of hard and resistant rock bands standing either vertically or at an angle which run parallel to the direction of the prevailing wind
Blowouts - These are hollows or depressions produced by wind deflation
Inselbergs - Residual hills consisting of hard and resistant rocks left behind after the rest of the surface has been eroded away
Desert Pavements - The horizontal areas of bare polished rock formed by the scouring action of quartz
Ventifacts - Heavier rock blocks left behind after wind has carried away all of the material
Wind depositional features associated with deserts - Sand dunes, seifs, barchan, ripples, loess
Sand Dunes - Are hills of sand which have been deposited by the wind in a desert
Seifs - Are long narrow ridges of sand which lie parallel to the direction of the prevailing wind
Barchans - Crescent shaped sand dunes that are formed by an obstacle in the desert like a rocks
Loess - Are a sediment formed by the accumulation of wind-blown particles that were carried by the wind beyond the desert limits
Ripples - Small wavy structures commonly found between sand dunes
Formation of sand dunes (or barchans and seifs) are influenced by - The extent of vegetation cover, the size of the sand particles, the relief of the desert, the velocity of the wind
Artificialforces
Soil
Soilformation
Soil - A natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics
Processes of soil formation -
Weathering of rock to produceregolith
Regolith - Loose broken material due to weathering of rock or deposition of alluvium, drift loess and volcanic material
Formation of topsoil by adding water, gasses, living organisms, and decayed organic matter(humus)
Five major factors of soil formation - Time, parent materials, climate, living organisms, topography
Soil composition andproperties
Components of soil - Organic matter (biota, 45%), inorganic matter (5%), soil water (25%), soil air (25%) Organic Matter - Made of decomposed plant and animal remains (humus) and living micro-organisms Inorganic Matter - Provide minerals required for plant growth
Soil Water - Derived from rainfall and is important for regulating temperature, dissolving nutrients
Soil Air - Plants and animals gain oxygen for metabolism from soil air
Soil profile and characteristics
Characteristics of soil are influenced by- Vegetation, parent rock, climate and weathering
Propertiesofsoil-Soilprofile,soildepth,soilcolour,soiltexture,soilporosity,soilstructure
Soil Profile - A vertical cross-section of the soil showing its horizons
Soil Depth - Varying properties depending on the maturity of the soil and nature of rocks below
Soil Colour - Colour is determined by mineralogical composition of the soil
Soil Texture - The degree of coarseness or fineness of a soil
Soil Porosity - Total volume of pores or empty spaces between particles of soil material
Soil Structure - Refers to the arrangement of soil particles
Sources of soil pollution - Atmosphere, daily human activity, industrial activity, farms
Atmosphere - Pollutants introduced through acid rain
Daily Human Activity - Garbage like plastic, metals, bottles, cans are dumped on the soil Industrial Activity - Chemicals, radioactive materials and industrial waste are dumped Farms - Pesticides (DDT/fertilizers) and certain crops can damage the soil
Ways you can combat soil degradation - Good agricultural practices, mixed farming, crop rotation,avoid soil pollution, education of land users, avoid bush fires, ensuring soil moisture, avoid mass wasting Factorsinfluencingsoilfertility-Presenceofmineralplantnutrients,presenceofwater,presenceofair,
soil pH, soil, presence of colloids, presence of organisms
Loss of soil fertility - Leaching, over-cultivation, monoculture, soil pollution, soil erosion, mass wasting, loss of water in the soil
Simple soilclassification
Podzol - The group of soils which occur mostly in moist cool temperate climates
Clay Soil - Is a naturally occurring material composed primarily of fine-grained minerals
Humus - Refers to any organic matter that has reached a point of stability, where it will break down no further and might, if conditions do not change, remain essentially as it is for centuries, if not millennia
Laterites (Red Lateric Soil) - Are soil types rich in iron (causing red from oxidation) and aluminum, formed in hot and wet tropical areas
Leaching - Is the loss of plant nutrients from the soil, contributes to groundwater contamination
Loam - Is soil composed of sand, silt, and clay in relatively even concentration (about 40-40-20% concentration respectively)
Residual Mountains - Owe their origin mainly to denudation
Mulching - The practice of covering the soil with a layer of grass or plant remains
Advantages of mulching - Helps to conserve moisture in the soil by preventing evaporation, reduces loss of soil by erosion, rotting mulch adds organic matter to the soil, helps control the spread of weeds
Types of soil - Azonal, intrazonal, zonal
Azonal Soil - Are without well-developed characteristics due either to their youth or to some condition of relief or parent material which prevent soil development, Soils forming in recent eolian, alluvial and colluvial deposits are azonal
Intrazonal Soil - Have well defined soil profile characteristics that reflect the dominant influence of some factor of relief or parent material over the classic zonal effects of climate and vegetation
Zonal Soil - Soils with clearly distinguishable horizons which occur in definite regions of climate and vegetation
Soilerosion
Soil Degradation - Is the spoilage of the quality of soil through human activity. It is deterioration of the soil quality through loss of fertility, soil pollution, soil erosion and mass wasting
Soil Erosion - Is the physical removal of soil from one place to another by agents of erosion such as running water, wind, glacier, or waves
Soil erosion is caused by manmade and natural causes such as - Sheet erosion, gully erosion, splash erosion, rill erosion, climate, nature of soil, vegetation cover, topography, cultivation, excessive mining, construction activities, excessive deforestation by man, bush burning
Ways of preventing soil erosion - Contour farming, crop rotation, terrace farming, afforestation and reforestation, destocking, avoiding bush fires, growing cover crops
Ways to manage soil effectively - Education, training of farmers, planting better crops, afforestation/reforestation, reducing chemical use in farming/industry, recycling
Elementary surveying and mapmaking
Meaning and types ofsurvey
Forms of surveying - Chain/tape, prismatic compass, plane table, leveling, cadastral, geodetic
Chain Surveying - Is a method of plane surveying which deals with the measurement of linear horizontal distances. The distances covered in chain surveys are normally short and straight
Plane Table Survey - Is the science of measuring and fixing positions of distant objects by intersectionby considering the surface of the earth to be a plane (completely flat surface), curvature is ignoredPrismatic Compass Survey - Is the fixing of an objects position in the field by measuring the angles of
bearing between the line of magnetic north and the line of sight of the object
Leveling - Is the process of measuring height differences between points on the ground by determining the relative altitudes of the two points
Cadastral Surveying - The kind of survey which collects data about the ownership of property
Geodetic Surveying - Precise type of surveying which covers large areas considering the curvature of the earth, uses triangulation/traversing/trilateration/leveling/astronomical direction fixing
Leveling - A process of determining the differences in elevation between two points
Uses of leveling - Construct contour maps, find the best level at which you should erect a building, create longitudinal section of roads/railways/canals/pipes/sewers in urban areas, determine proper human settlements
Tools used for leveling - Leveling instruments (i.e. theodolite, abney level, clinometer, alidade, dumpy level, tilting level etc), leveling staff, chain or tape, pegs, field sheets
Purpose of plane surveying - Determine horizontal distances between two or more points on the surface, to locate physical and nonphysical features on the surface, direction of various features of the surface, determine the area of a given region
Tools for a plane table survey - Plane table, alidade, plumb bob, trough compass, spirit level, clinometer
Advantages of a plane table survey - It is the best kind of survey used to measure and fix positions of distant objects, it is quick/accurate and allows quick sketching of details, it can cover very large land areas, less accumulation of errors than chain surveying, uses instruments which are easy to use, useful for cartography, booking is not required
Disadvantages of a plane table survey - Not suitable for a small area of land, not suitable for undulating surfaces, cannot be used during damp or rainy seasons, requires alidade which requires skills to use, a simple math error can cause all angle measurements to be incorrect, some instruments are expensive
Equipment used for prismatic compass surveying - Two prismatic compasses, ranging poles, tape measures, chains, metal markers, chalk, field sheets
Advantages of prismatic compass surveying - Rapid method, check can be made on all compass bearings, cumulative error is reduced/easily fixed, objects can be pin-pointed with accuracy, method can be combined with other methods
Disadvantages of prismatic compass surveying - Transport is needed if surveying over long distances, human error is involved in observations, magnetic rocks may affect readings
Alidade - Is a device that allows one to sight a distant object and use the line of sight to perform a task such as to draw a line on a plane table
Surveying - The science of measuring and recording distances, angles and heights on the Earth’s surface to obtain data from which accurate plans and maps are made
Topographic Maps - colour contour maps showing the physical and manmade features such as rivers/roads/mountains/valleys/railways
Traversing - Consists of a series of lines whose lengths and directions are measured, connecting points whose positions are determined used to establish data benchmarks
Triangulation - Consists of a series of connected triangles which overlap each other, used to reduce the number of measurements that need to be taped or chained
Trilateration - Is the use of electronic distance measuring equipment to directly measure the lengths of the sides of triangles from which angles can be calculated
The three types of topographic surveying are chain surveying, prismatic compass surveying, and plane tablesurveying
Bearing - The direction of a place in degrees from another place
Bearing of SW is - 225º
ESE - 112.5 º
Chainsurvey
Instruments used in chain surveying - Chain, tape, surveyor’s band, ranging poles, cross staff, pegs, arrows, optical square, notebook
The Chain - This chain is made up of pieces of steel which are connected by rings
The Tape - Used to measure horizontal distance on the ground
Surveyor’s Band - A long graduated strip made from steel or plastic, rolled in a metal frame
Ranging Poles - Locates a place temporarily during the chaining process
Cross Staff - Used to set a perpendicular line or right angles from the main line of survey
Pegs - Their major function is to mark points permanently on the ground
Arrows - Steel skewers which mark and locate temporary positions on the surface Optical Square - Used for setting offsets from right angles from the line Notebook - Good notebook for recording or booking all fieldworkinformation
Preparing a chain survey - Must be well informed about the nature and location of the area, land configuration, presence of buildings or natural obstacles, preparation of instruments and personnel, prepare working schedule,transportation
Advantages of chain surveying - Used to map small areas on flat ground, simple to conduct, used to add details to existing maps, needs few people to set up, uses simple tools like pegs, applicable to compass surveying also, only survey for measuring distances (the others measure angles and heights), does not require a lot of mathematicalcalculations
Disadvantages of chain surveying - Time consuming, subject to the accumulation of errors
Map reading andinterpretation
Concept of mapreading
(Not in study guide)
Reading and interpreting topographicalmaps
(Not in study guide)
Photograph reading andinterpretation
Types of photographs
(Not in study guide)
Reading and interpretingphotographs
(Not in study guide)
Application ofstatistics
Concept ofstatistics
Importance of studying statistics - It helps to summarize massive data in simple figures, simplifies the process of data interpretation, helps to represent data in visual ways like charts and maps
Sources of Data - Primary sources, secondary sources
Primary Data Sources - Data collected directly from the field, also known as first hand data
Secondary Data Sources - Data obtained from other people’s findings i.e. from books, journals etc
Continuous Data - Are number that can be expressed with infinite figures of possible values that fall between any two observed values
Data - Exact numerical values collected and arranged for a certain purpose
Discrete Data - Consists of separate and indivisible categories of data
Group Data - Are values given in a range of numbers, data falls into certain classes
Single Data - Are statistics or values given for each individual item in a sample
Simple statistical measurement andinterpretation
Use the following data to draw a group bargraph:
Contribution of Agriculture to the Gross Domestic Product (GDP) in East Africa (in percentage)
Year
Tanzania
Kenya
Uganda
1954
64
47
67
1958
59
42
64
1960
61
40
61
1965
54
38
59
To draw this graph you must first think about what the x and y axes will be. The x axis will be years because this will group together the percentages from each country. The y axis will be percentage because this is the value being compared between the various countries. A grouped bar graph is chosen because it shows the difference between each country’s GDP by year clearly.
Advantages - Enable easy comparisons, easy to interpret, no complicated calculations, detailed, contrasts clearly, gives visual impression about thetotality
Disadvantages - Consumes time, does not give accurate impression of totals, erroneous conclusions can be made depending on the scale used, uses manycolours
Use the data below to draw a compound line graph and a compound bargraph
Year
Maize
Coffee
Beans
Sorghum
Wheat
2001
300
550
720
800
850
2002
290
540
530
810
830
2003
310
520
650
750
780
2004
250
530
660
700
770
2005
270
525
700
800
850
To draw a compound line graph you first plot the x and y axes. You start with the smallest number to draw the bottom portion of the graph (in this example it is maize), then you choose the next lowest until you have drawn a line for each variable. After this you shade down to the next line until you have completed
Advantages of compound graphs - Useful in comparing many variables, attracts readers with colours, detailed information is provided
Disadvantages of compound graphs - Needs knowledge of mathematics, needs more time to construct, if the same shading is used it may mislead the interpreter
Use the data below to show the enrolment of form 5 students using a divergent line and bargraph
Year
Number of students
1980
100
1981
150
1982
175
1983
200
1984
225
1985
300
To construct a divergent line or bar graph you must first calculate the mean deviations. This is done by calculating the mean then finding the difference between the number of students and the mean deviation.
Finding the mean deviation Step 1: Find the mean
100 150 175 200 225 300
Mean (average) =
191.7
6
Step 2: Find the deviation for each data
Ex. 1981
Ex. 1983
150 - 191.7 = -41.7
200 - 191.7 = 8.3
Year
No of Students
Mean Deviation
1980
100
-91.7
1981
150
-41.7
1982
175
-16.7
1983
200
8.3
1984
225
33.3
1985
300
108.3
Since the answers are both negative and positive (because they lie on either side of the mean), you will use a graph that shows both positive and negative values, the divergent bar graph. You can also use a line graph, or a simple bar graph.
Advantages: It shows the increase or decrease of values over time, it is used for comparisons
Disadvantages: It does not deal with real numbers but rather only with mean deviations, it also needs extra calculations and is difficult to construct
Construct a line graph and bar graph from the data below and discuss the definition of a line graph as well as its maintypes
Line Graph - Is a graphical representation of data which uses a line to join the points of the data being represented
Four types of line graphs - Simple line graph, compound line graph, group line graph, convergent line graph
Year
1970
1971
1972
1973
1974
Coffee Production (Tons)
2050
2600
1800
1950
3000
Advantages - Easy to construct/draw, illustrates variations, no difficult calculations, easy to interpret/read, saves, simple visual impression, wide variety of uses, exact values are easily estimated
Disadvantages - Inaccurate deductions can be made, easy to confuse X and Y variables, little space where X and Y axes meet, cannot represent more than one item
Create a pie chart using the data below of car types used inTanzania
Period
Datsan
Land rover
Isuzu
Toyota
Others
8:30-10:30 AM
100
150
300
240
80
2:30-4:30 PM
40
60
70
20
50
6:30-8:30 PM
120
130
90
140
120
Total
260
340
460
400
250
To create a pie chart you must calculate the degrees that each portion of the pie represents
Step 1: Calculate the sum total of angles. Add up the values in the Total row.
260 + 340 + 460 + 400 + 250 = 1710
Step 2: Calculate angles of each car type and then draw them with a protractor
Ex. Datsan
260 * 360º 54.7º
1710
Advantages - Easy to interpret, easy to construct, illustrates statistical information accurately, gives a good visual representation, useful for comparing various commodities/sectors/items
Disadvantages - Difficult to read for getting exact values, trends and directions of change in value cannot be deduced from a pie chart, time consuming to calculate and construct, difficult to interpret or draw when there are numerous items
Make a population pyramid graph from the followingdata:
Simply plot males on one side and females on the other with each row of the graph representing one of the columns of data. On the X axis you start with 0 in the centre and write marks on either side of it.
Age
0-4
5-9
10-
14
15-
19
20-
24
25-
29
30-
34
35-
39
40-
44
45-
49
50-
54
55-
59
60+
Male
6000
5000
4000
3700
3500
3400
3200
3100
3000
2800
2400
2000
1700
Female
6000
5800
4500
4200
4000
3900
3700
3600
3500
3200
3000
2500
2200
Advantages - Enables one to analyze the structure of a given population, forms a basis for predicting population structure in the future, used to estimate or evaluate current/future needs, easy to construct and interpret, used to compare structure of different populations, used to compare between males and females
Disadvantages - Involves a lot of calculation, not easy to choose convenient horizontal scales, five year age groups generalize groups, can take a lot of space if there are too many age groups
a) From the data below calculate the mean, mode, median, modal class, and standarddeviation
8, 22, 18, 20, 22, 8, 8, 13, 16, 21, 22, 30, 23, 16, 8, 4, 6, 2, 10, 12, 14, 15, 16, 22, 22, 27, 26, 22, 18, 4
First order all of the numbers
2, 4, 4, 6, 8, 8, 8, 8,10, 12, 13, 14, 15, 16, 16, 16, 18, 18, 20, 21, 22, 22, 22, 22, 22, 22, 23, 26, 27, 30
Finding the Mean (Average) Step 1: Sum all numbers
nums 475
Step 2: Divide by number of values
Number of values = 30
Step 3: Divide sum by number of values
475 15.8
30
Finding the Mode
Step 1: Find the value with the highest frequency
Mode = 22, it was found 6 times
Finding the Median
Median - The median is the number which divides the distribution of numbers into two equal parts (halves)
Solution: Since there are 30 numbers, the middle value is in between the 15thand 16thnumbers, so you must find the average of these two values. In this case the 15thand 16thvalues are the number 16
16 16 16
2
Mean (Avg) = 15.8 Mode = 22
Median = 16
b) Finding the modal class and standard deviation for the above set ofnumbers
Class Interval
F
X
F * X
X2
F*X2
0 - 4
3
2
6
4
12
5 - 9
5
7
35
49
245
10 - 14
4
12
48
144
576
15 - 19
6
17
102
289
1734
20 - 24
9
22
198
484
4356
25 - 29
2
27
54
729
1458
30 - 34
1
32
32
1024
1024
f 30
fx 475
fx 29405
How to calculate the values found in the table above:
Class Interval
Chosen with a class size of5
F is the frequency of numbers
Found by looking at the ordereddata
X is the average of each class level
Ex. Class 10-14
X = 12
XF = 4 * 12 = 48
X2is the square of X
Ex. Class 10-14
X = 12
X2= 122= 144
FX2is the product of F times X2
10 14 7
2
FX is the product of F times X
Ex. Class 10-14
F = 4
Ex. Class 10-14
F = 4
X2= 144
F * X2= 4 * 144 = 576
Finding the Modal Class
The Modal Class is the class with the highest frequency (F) Class 20 - 24 has the highest frequency (F) of 9
Calculating standard deviation
There are two formulas for calculating standard deviation; the summations come from the table above
f 30
fx 475
fx 29405
Formula 1
Formula 2
fx2 fx2
SD = f f
9405 4752
SD =
30 30
SD= 313.515.52
SD = 63.6
SD = 7.9
fx2
fx
SD = n
n 1
4752
9405
SD = 30
30 1
9405 7520.8
SD =
29
SD = 64.9
SD = 8.0
Form 4
Introduction toresearch
Concept ofresearch
Types of Research - Descriptive, analytical, applied, fundamental (pure), quantitative, qualitative, conceptual, empirical
Descriptive - Research which deals with description a state that existspresently
Analytical - Use of facts or existing information and then analyzing them to make critical evaluations Applied - Aims to find a solution to an immediate problem facing a society or an organization Fundamental - Research which deals with generalizations or formation oftheory
Quantitative - Research which deals with the measurement of quantity or amount in numerical form
Qualitative - Deals with the quality of a phenomenon
Conceptual - The research which deals with abstract ideas or theory, so as to develop new concepts
Empirical - The research which relies on experience or observation without regarding system or theory
Objectives of Research - To be familiar with a phenomenon, to reveal accurate features of certain aspects of social life, test or approve hypotheses of casual relationships between phenomena
Importance of Research - Provides policy makers with accurate information about the subject matter, used to provide accurate solutions to social problems, used to direct social activities, providing reliable information to the data bank, members of society become well informed about their society
The benefits and problems of research - Benefits: Helps remove preconceived ideas in the researchers mind, creates a spirit of investigation, finds accurate solutions to problems, provides sources for future
research, used to improve production Problems: Takes a lot of time, research may be unsuccessful or useless, research is often only applicable to intellectuals
Why conducting field research is important - The method is systematic, objective, specific to a certain problem, encourages collection of original data
Problems that can be encountered during field research - Transport problems, climatic problems, language problems, instruments not being available, diseases, lack of human needs
Objectives of field research - Discovery of new knowledge, explanation of phenomena, description of a phenomenon, prediction of new principles or theories, theory development
How to conduct field research - Identify the problem, form a hypothesis, collect data, analyze data, data recording and presentation, testing the hypothesis, generalization
How to prepare yourself for field research - Understand the problem in well defined terms, know objectives of the research, awareness of geographical region, know types of data required and how to obtain them, know the sample of population to be studied, prepare tools for analysis, prepare a budget/work plan/time schedule
Important uses of research findings - Used to solve social problems, used by agricultural experts, preparing teaching materials and methods, improving governance, helps distribute social services, controlling diseases, to report data to the population, used by businessmen to develop business
Sampling Techniques - Method of getting samples from a population; random sampling, systematic sampling, stratified sampling
Quantitative Research - Based on the measurements of quantities or amounts of variables of a phenomenon
Research - Is the systematic collection of data used to understand a problem orphenomenon
ResearchTools-Methodsofdatacollectionincludingobservation,interviews,questionnaires
Non-probability sampling (Non-random sampling) - The elements chosen in the sample are not given an equal chance of being selected. (E.g. Handpicked sampling, snowball sampling, volunteer sampling)
Probability Sampling (Random Sampling) - States that each element in the population has an equal chance of being selected. (E.g. Simple random sampling, systematic sampling, stratified random sampling, cluster sampling)
Sampling - Is the process of selecting a small portion of the total population which will represent the entire population statistically
Hypothesis - Is a statement of speculation about the outcomes of research. It is the expected result of research by the researcher before going to the field to collect data
Field Research - Process of collection of data in a systematic manner with the aim of solving a problem
Stages of researchwork
Stages of conducting research - Identify problem, formulate hypothesis, labeling variable, establish a study design, data collection, analysis of information, report writing, conclusion
Research Techniques - Observation, measurement, interview, questionnaires, focus groups
Observation - Use of eyes to look at phenomena to record what is seen
Measurement - The way data is obtained by using equipment
Interview - Conduct a verbal interaction between an interviewer and interviewee
Questionnaire - Prepared questions to be answered by a respondent set by a researcher
Focus Group Discussion (FGD) - Involves intensive discussion about a particular issue done in a small group of people
Types of Hypothesis - Null, alternative
Null - One that is stated in negation, can be said to be true or false
Alternative - Indicates an actual expectation or relationship
Characteristics of a good hypothesis - States clearly the relationship between the variables, must provide sound rationale, consistent with commonly accepted notions, must be testable, must be related to empirical phenomenon, must be consistent with purpose of research, simple and concise
Purpose of hypotheses - Provides direction, ensures collection of evidence to answer research problem, sensitize the investigator to certain aspects of the situation, enables researcher to access information they have collected from respondents, permits researcher to understand problem with greater clarity and use it to find a solution, provides a framework for the ultimate conclusion of the research
Research Proposal - A systematic plan which plans what will be needed to accomplish the main objective of the research
Functions of a research proposal - Guideline to show how to proceed with a project, shows where the research should end, shows how the research will be evaluated in the future
Components of a research proposal - Title, problem and setting, hypothesis, literature review, work plan, budget chart, references
Qualities of a good research proposal - Should be clearly written, precise, reasonable length, worth time/money being used
Climate and naturalregions
World climatic types and theircharacteristics
(Not present in exams)
Natural regions of theworld
Trees of tropical rainforests and coniferous forests are evergreenTropical rain forests consist primarily of hard wood
Humanpopulation
Concepts of population
Age Structure of a Population - The distribution of ages of people in a society Birth Rate - The number of live births per year per 1000 people in the population Death Rate - The number of deaths per year per 1000 people in the population
Family Planning - Is the process of improving conditions of the family by ensuring an appropriate number of children and a proper spacing of time between one child and another
Growth Curve - The curve shape produced when the rate of growth of an organism or population is plotted on a graph
Infant Mortality Rate - Number of deaths of children below one year old per 1000 people in the population
Landlocked Countries - Countries without suitable harbours or access to oceans
Population - Is the number of people available in a given geographical area
Rural-Urban Migration - Movement of people, especially young people, from rural areas to towns and cities
Urbanization - Is the process of transformation in which a rural area develops into a town, from trade, modern buildings, population increase
Factors determining age structure in a population - Birth rate, death rate, infant mortality rate, migration, marriage status and rates
Explain the effects of rapid population growth on small scale agriculture - Causes deforestation, desertification, land conflict, food shortage, land degradation, water pollution, soil pollution
Effects of overpopulation on human and natural resources in East Africa - Not enough doctors/teachers for the large population, overexploitation of natural resources like water/land, lower standards of living, poor housing/social services
Characteristics of human populations - Population size, population density, population distribution, sex ration, age distribution, population growth rate, population change
Factors that influence population distribution - Physical factors like topography/climate/soil/vegetation, pests/diseases, war/government policies, economic factors like employment/industry
The aims of introducing family planning - To improve the living standards of the family, control population pressure, improve health of mothers and children, avoid STDs and unwanted pregnancy
The main problems facing family planning in Tanzania - Poverty, ignorance, cultural beliefs, religious beliefs, poor means of transport and communication to spread the message, lack of education, poor organization of groups spreading this message, laws such as allowing girls to marry at 15
Factors influencing rapid human population growth and distribution - Availability of food supplies, availability of clean/safe water supplies, pollution-free environment, availability of health services, availability of social services i.e. schools/markets, availability of infrastructure, availability of employment
Factors influencing population changes - Migration, death, birth, governmental policy
Settlements
Concept ofsettlement
Linear Settlement - Is a pattern of settlement where homes are along a road or railway system Nucleated Settlement - Is a pattern of settlement where homes are situated close to each other Scattered Settlement - Is a pattern of settlement where homes are situated far apart
Migration - Is the movement of people from one region to another
Growth ofsettlements
Settlement patterns are influenced by - Physical Factors: Climate/soil/topography, biological factors: pests/diseases/vegetation, Political Factors: War/policies/economics/culture
Explain the basic factors involved in setting up rural settlements - Availability of land and economic activities, climate, availability of water sources, vegetation, topography, pests/diseases, safety
Functions in an urban settlement - Administrative and economic centres, defensive functions, provision of higher education/health services, production centres, markets, entertainment, financial services
Negative impacts of rural-urban migration - Depopulation, failure of local economic activities, shortage of food production, breaking of family ties, environmental pollution in urban areas, unemployment, inadequate social services, increase in crime in urban areas as people struggle to survive
Main factors causing rural to urban migration - Absence of employment opportunities, land shortage, poor health services in rural areas, poor infrastructure, poor educational services, low income
Pure Nomadic Pastoralism - Pastoralists have no permanent residence and are in constant movement grazing from one place to another
Semi-nomadic Pastoralism - Farmers have permanent residence but during the dry season they travel long distances to look for pasture and water, have some level of cultivation to supplement income/food
The disadvantages of nomadic pastoralism in northern Kenya - Contributes to soil erosion from movement of herds, desertification from eating vegetation, does not allow farmers to settle, source of conflict between farmers and nomads over land use, animal diseases spread easily
Characteristics of nomadic pastoralism in East Africa - Not confined to a single area, animals are for subsistence purposes, poor health of animals, causes soil erosion/desertification, conflict between pastoralists and farmers, requires little capital
How to improve pastoralism in East Africa - Provision of education to farmers of modern ways of keeping livestock, adopt a range system to avoid desertification and soil erosion, provide health services to animals, provide storage facilities to farmers and livestock producers, improve transportation, have separate land for farmers and pastoralists
Factors which cause the different types of internal migration - More developed areas have more job opportunities, low agricultural productivity, poverty/hunger/underemployment, rapid increase in population, development of projects, government policies, war/violence, better social/health services
Environmental issues andmanagement
Concept ofenvironment
Ecosystem - Is a network of living organisms and non-living things interacting with each other
Features adopted by plants to survive in hot deserts - Long roots to penetrate to underground water, succulent leaves and stems for storage of extra water, waxy or needlelike leaves to prevent loss of water, seeds which are dormant for years until rainfall occurs
Cacti - Typical plants of a hot desert area, have long roots, thorny steps, needle shaped leaves, wax or hair
Importance ofenvironment
(Not present in exams)
Importance of the environment - Natural resources, human health, farming, tourism, beauty, biodiversity
Environmentalproblems
Environmental problems facing Tanzania - Environmental pollution from industry/agriculture/human activities, desertification, soil erosion, land degradation, deforestation from economic activities like charcoal production, loss of biodiversity
Examples of environmental hazards - Earthquakes, floods, bush fires, drought, volcanic eruption, tsunami, pollution, environmental degradation, desertification, deforestation
Environmental Degradation - The gradual or rapid decline of the quality of the environment required for animals or plants to live
Environmental Hazards - Are toxic materials or incidences which are harmful to humans or other animals, they can be caused by human activity or by natural occurrences
Acid Rain - Is rain which results from the mixture of moisture in the air with oxides of nitrogen and sulfur forming nitric acid, sulphuric acid, and carbonic acid
Effects of acid rain - Death of plants and animals, fills lakes/rivers/dams with acidic water, reduces quality of soil for agriculture, speeds up the rate of erosion of rocks, causes corrosion of infrastructure
Deforestation - The excessive massive cutting down of trees by humans for economic activity
Forestry - Is an economic activity which deals with the production of wood products and cutting of forests
Environmentalconservation
Measures taken to solve environmental problems in Tanzania - Environmental education in schools/colleges/universities, reforestation, protection of national forests, laws, restriction of harmful chemicals, restrictions on hunting
Ways to avoid environmental degradation in Central Tanzania - Afforestation and reafforestation, destocking, proper farming methods, alternative sources of fuel (non charcoal), encourage irrigation, diversify economic activities, increase education
Explain soil conservation measures in Kondoa District - Destocking, crop rotation, afforestation, reforestation, intercropping, filling gullies with brushwood
Causes of the loss of biodiversity - Human activities like agriculture or industry, expansion of grazing land into new habitats, urbanization, overexploitation of forests/oceans, fishing with dynamite, pollution
Biodiversity - Refers to the variety of life on earth in all its forms
Coniferous - They are cone-bearing seed plants with vascular tissue; all extant conifers are woody plants, the great majority being trees with just a few being shrubs
Deciduous - Consists of broad leaves and are found in temperate regions
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