SOIL FORMATION

SOIL FORMATION.

     Soil formed through the process of weathering of parent rock. Major portion of soil especially the minerals are formed from the parent rock or parent materials.

  There fore soil formation can be defined as; the Genesis or evolution of soil from the parent materials. The process of soil formation is continous process which takes place through the process of parent rocks.                                                     

 
        Weathering process is the process of breaking down of parent rock material into small particles. Weathering process can be physical or chemical process.

    As weathering process taking place the small particles of parent rocks mixed up with organic materials from dead animals and plants, water, air and living organisms to make up soil.
       
                Factors which influence soil formation.
 The following are factors which affect soil formation

•   The nature of parent materials

•   The climate of the area

•   living organisms especially vegetation

•  The length of time that parent materials is exposed to soil formation process

•  the topography of the area where these process take place.

 1.Nature f the parent materials.
    Nature of parent materials which weathering occur has alot of influence in soil.
 The speed at which weathering occur it depend on type of parent rock material, also the size of soil particles depends more on nature of parent parent rock.

   There fore nature of parent materials influence both chemical and physical properties of the soil.

2. Climate.
      Climate of the area also influence the soil formation. Climate include temperature and rainfall of the area. The amount of rainfall and temperature of the area determine the kind of weathering in that place. Weathering can take place through chemical or physical process it will depend on type of climate of the area.

      Rocks expand and contract when temperature rise and full respectively. This cause parent rock to became weak gradually. The speed of microbial activities also increase with dense vegetation, high temperature and more rainfall.

3. Living organisms
   Animals especially micro organisms and plants roots play very important part in soil formation. Plant roots growing in rock crevices present a force which cause the rocks to crack. Also organic materials which are found in soil are due to daed living organisms.

4. Time
   Parent materials which has been exposed to weathering agents for a longer time is generally more weathered than one which has been weathered for a short time. And this is why some soil Sid to be young soil while others are said to old soil.