Published on May 14, 2010
Slide 1: The thin layer of grainy substance covering the surface Of the Earth is called Soil. Soil Soil is the upper layer of the crust and is closely Linked to land. Landforms determine the type of soil Slide 2: Soil is also known as earth Soil is formed as a result of weathering of rocks Weathering is the decomposition of Earth rocks, soils and minerals through direct contact with the planet's atmosphere. Slide 3: The right mix of minerals and organic matter make The soil fertile The right mix of minerals and organic matter make The soil fertile Slide 4: Soil Profile is a representation of the different layers of The soil. Soil is a living system Slide 5: Top Soil Sub Soil, Sand Weathered Rock Parent Rock Slide 6: Soil Formation Soil Parent Rock Relief Flora, Fauna, Microorganisms Time Climate Slide 7: It takes hundreds of years to make just one centimetre of soil Slide 8: Types of Soil According to colour, thickness, texture, age, chemical composition and physical properties Alluvial Soil Black Soil Red & Yellow Soil Laterite Soil Arid Soil Forest Soil Slide 9: Alluvial Soil The most widely spread and important soil Spreads over the entire Northern Plains Deposited by the three river systems Can be seen in the deltas of eastern rivers too Slide 10: According to age, alluvial soil can be classified into old alluvial (Bangar) and new alluvial (Khadar) New alluvial soil is more fertile than the old alluvial Has adequate proportion of potash, phosphoric acid and lime Ideal for sugarcane, paddy, wheat and other cereal and pulse crops So, the regions of alluvial soil are thickly populated and intensively cultivated Slide 11: The soil is black in colour because it is volcanic in origin Black Soil Created from igneous rocks, and is called ‘regur soil’ It is ideal for growing cotton and so called black cotton soil. Black soil cover parts of Maharashtra, Saurashtra, Malwa, Madhya Pradesh and Chhattisgarh Slide 12: Red & Yellow Soil Red and yellow soil develops on crystalline igneous rocks in the areas of low rainfall in the eastern and southern parts of Deccan Plateau. Also found in parts of Orissa, Chhattisgarh, south of middle Ganga plain and the eastern piedmont zone of Western Ghats Slide 13: The red colour is because of the diffusion of iron in the form of iron oxide in the crystalline and metamorphic rocks It looks yellow when it is in the hydrated form Slide 14: Laterite has been derived from the Latin word ‘later’ that means brick. Laterite Soil Slide 15: Develops in areas of high rainfall and high temperature. The humus content in the laterite soil is less because the micro-organisms and decomposers get destroyed in the high temperature Mainly found in Kerala, Karnataka, Tamil Nadu, Madhya Pradesh, Hilly areas of Orissa and Assam After taking soil conservation measures, this soil is suitable for tea, coffee, cashew nut etc. Slide 16: Arid Soil The colour of arid soil ranges from red to brown Generally sandy in texture and saline in nature In some areas salt content is high and so, salt can be obtained by evaporating the water Slide 17: Due to high temperature, dry climate, evaporation is faster and the soil lacks humus and moisture. After taking proper irrigation measures, this soil can be used for agriculture.