Agriculture JSS2

Week 3


Factors affecting soil formation are;

  1. Parent materials i.e origin of the soil
  2. Climate-Such as rainfall, temperature and wind.
  3. Topography
  4. Living matter or biotic factors-micro organism, roots of growing tree
  5. Time

Parent materials: Parent material is the unconsolidated mineral and organic deposits in which soils are developing. It determines the mineralogical composition and contributes largely to the physical and chemical characteristics of the soil. The kind of parent material also influences the rate at which soil forming processes take place.

Climate: Climate, particularly temperature, precipitation and frost action have a profound influence on the soil forming processes which occur within a region. The kind of climate largely determines the nature of the weathering processes that will occur and the rates of these chemical and physical processes. It directly affects the type of vegetation in an area which in turn will affect those soil forming processes related to vegetation. Plymouth County is in a transitional climate zone with conditions characteristic of both humid marine and humid continental climates

Topography: The shape of the land surface, its slope and position on the landscape, greatly influence the kinds of soils formed. In Plymouth County soils that formed in similar parent materials with the same climatic conditions exhibit differences as a result of their position on the landscape. These differences are largely a result of varying drainage conditions due to surface runoff or depth to water table.

Organism: All living organisms actively influence the soil forming process. These organisms include bacteria, fungi, vegetation and animals. Their major influence is the effect on the chemical and physical environment of the soils

The formation of soils is a continuing process and generally takes several thousand years for significant changes to take place. The soils of Plymouth County began to develop immediately after the ice retreat of the last glaciation (Pleistocene), approximately 14,000 years ago. The soils are considered to be relatively young soils with slight alteration of parent material and weak soil horizon development. Most of the soil orders mapped in Plymouth County are Inceptisols, Entisols, and Spodosols.


List and explain two factors of soil formation?

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