Lithosphere is outer mantle of solid earth consists of minerals in the earth’s crust and the soil. Soil is formed by the combination of climate, plant and animals life. The major components of soil are mineral matter, organic matter, water and air. The constituents of soil are mineral matter 40-50%, water 20-50%, air 10% and organic 5%. There are kinds of rocks -Igneous rock, sedimentary rocks and metamorphic rocks.
Igneous rocks are formed by cooling, hardening arid crystallizing of various kinds of lavas. They chiefly contain feldspar minerals and quantize. The granites are the common igneous rock.
It is derived from rocks and it is formed by consolidation of fragmentary rock materials deposited by water. The common sedimentary rocks are conglomerate, sandstone and limestone etc.
These are formed from the igneous or sedimentary rocks by the action of intense heat and high pressure. The examples are granite, quantize, sand stone marble etc.
Types of soil:
Alluvial soils are costal alluvial and coastal sands. it is the most fertile soil.
It varies in depth and is black cotton soil found in Maharashtra, Madhya Pradesh and Tamil Nadu. It contains highly calcium and magnesium carbonates.
Red soils found largely in Tamil Nadu a Karnataka, Goa, Daman and Diu. The ancient crystalline and metamorphic rocks on meteoric weathering have given rise to red soils.
Lateritic soil is a composition hydrated oxides of aluminum and iron with small amount of manganese oxides; it is derived from the atmosphere weathering of several types of rocks.
Late rites are found summits of hills Karnataka, Kerala and M. P. late rites are very poor in time and magnesia, deficient in nitrogen.
Desert soils are composed on quartz, feldspar etc.
It contains toxic concentrations soluble salts. It is electrical conductivity in nature.
It does not contain any amount of natural salts and less electrical conductivity in nature.
Adverse effects of soil salinity:-
- Cause low yields of crops.
- Difficulties in construction of buildings and roads.
- Excessive run off and floods owing to flow infiltration resulting in damage of crops.