Indian Agricultural: Growth, Generation, Policy & Problem Indian Agricultural | Page 15

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03. Agricultural soil
Agricultural soil science studies the chemical, physical, biological, and mineralogical composition of
soils as they relate to agriculture. Agricultural soil scientists develop methods that will improve the use
of soil and increase the production of food and fiber crops. Emphasis continues to grow on the
importance of soil sustainability. Soil degradation such as erosion, compaction, lowered fertility, and
contamination continue to be serious concerns. They conduct research in irrigation and drainage,
tillage, soil classification, plant nutrition, soil fertility, and other areas.
Soil Fertility
Agricultural soil scientists study ways to make soils more productive. They classify soils and test them
to determine whether they contain nutrients vital to plant growth. Such nutritional substances include
compounds of nitrogen, phosphorus, and potassium. If a certain soil is deficient in these substances,
fertilizers may provide them. Agricultural soil scientists investigate the movement of nutrients through
the soil, and the amount of nutrients absorbed by a plant's roots. Agricultural soil scientists also
examine the development of roots and their relation to the soil. Some agricultural soil scientists try to
understand the structure and function of soils in relation to soil fertility. They grasp the structure of soil
as porous solid. The solid frames of soil consist of mineral derived from the rocks and organic matter
originated from the dead bodies of various organisms. The pore space of the soil is essential for the
soil to become productive. Small pores serve as water reservoir supplying water to plants and other
organisms in the soil during the rain-less period. The water in the small pores of soils is not pure
water; they call it soil solution. In soil solution, various plant nutrients derived from minerals and
organic matters in the soil are there. This is measured through the cation exchange capacity. Large
pores serve as water drainage pipe to allow the excessive water pass through the soil, during the
heavy rains. They also serve as air tank to supply oxygen to plant roots and other living beings in the
soil. In short, agricultural soil scientists see the soil as a vessel, the most precious one for us,
containing all of the substances needed by the plants and other living beings on earth.
Soil Preservation
In addition, agricultural soil scientists develop methods to preserve the agricultural productivity of soil
and to decrease the effects on productivity of erosion by wind and water. For example, a technique
Ramesh Kumar P