Role of Living Organisms in Soil Formation

Role of Living Organisms in Soil Formation

Soil formation means both the production of parent material and soil profile development. The process of weathering and soil profile development occurs simultaneously.
The formation of soil happens over a very long period of time. It may take thousands of years. Soil is formed as results of weathering of rocks and minerals. The surface rocks break down into smaller pieces through a process of weathering and is then mixed with organic matter. Over time this creates a thin layer of soil and then lower plants grow and soil development is enhanced. Later on higher plants grow and attract animals. When the plants and animals die their bodies decay/decompose. Decaying matter makes the soil thick and rich. This continues until soil is fully developed.
The activities of living plants, animals and the decomposition of their wastes and residues have marked influence on soil development. Soil organisms play a major role in soil profile differentiation through
Organic matter accumulation
Profile mixing
Nutrient cycling
Soil structure stability
Burrowing animals such as moles, earthworms, ants and termites are highly important when they exist in large numbers. Soils having large numbers of burrowing animals have fewer but deeper horizons. Microorganisms present in the soil attack plant and animals residues producing organic materials. These microorganisms along with an abundance of plant roots help to bind soil particles into stable aggregates. Similarly, certain microorganisms can fix atmospheric nitrogen into compound usable by plants.




Location: Pakistan

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