Soil

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Soil as resource

What is soil?:

What is soil? Top most layer of earth crust consisting of organic and inorganic matters is called soil. Soil is a renewable resource. Soil is a living system. It is the medium of plant growth and supports different types of living organisms on the earth. Unweathered parent bed rock. Top soil the upper soil layer. Subsoil weathered rocks sand and silt clay. Substratum weathered parent rock material.

Factors of Soil formations:

Factors of Soil formations Relief, Parent rock or bed rock, Climate, Vegetation and other forms of life. Change in temperature, Chemical and organic changes.

Classification Soils:

Major types of Soils found in India. Alluvial Soil Black Soil Red and Yellow Soils Laterite Soils Arid Soils Forest Soils. Classification Soils

Alluvial Soils:

Alluvial Soils Most widely spread: The entire northern plains are made of alluvial soil. Piedmont plains in the upper reaches of the river valley, the soils are coarse are Duars , Chos and Terai . According to their age alluvial soils can be classified as old alluvial ( Bangar ) and new alluvial ( Khadar ).

Black Soils:

Black Soils Climatic condition along with the parent rock material are the important factors for the formation of black soil. This type of soil is found in the Deccan trap (Basalt) region. They are well-known for their capacity to hold moisture. In addition, they are rich in soil nutrients.

Red and Yellow Soils:

Red and Yellow Soils Red soil develops on crystalline igneous rocks in areas of low rainfall in the eastern and southern parts of the Deccan plateau. Yelllow and red soils are also found in parts of Orissa, Chhattisgarh middle Ganga plain. It looks yellow when it occurs in a hydrated form.

Laterite Soils:

Laterite Soils This is the result of intense leaching due to heavy rain. Humus content of the soil is low because most of the micro organisms, particularly the decomposers, like bacteria, get destroyed due to high temperature. These soils are mainly found in Karnataka, Kerala, Tamil Nadu, Madhya Pradesh, and the hilly areas of Orissa and Assam.

Arid Soils:

Arid Soils In some areas the salt content is very high and common salt is obtained by evaporating the water. Due to the dry climate, high temperature, evaporation is faster and the soil lacks humus and moisture. The lower horizons of the soil are occupied by Kankar because of the increasing calcium content downwards.

Forest Soils:

Forest Soils These soils are found in the hilly and mountainous areas where sufficient rain forests are available. The soils texture varies according to the mountain environment where they are formed. They are loamy and silty in valley sides and coarse grained in the upper slopes. In the snow covered areas of Himalayas, these soils experience denudation and are acidic with low humus content.

THE IMPORTANCE OF SOIL :

THE IMPORTANCE OF SOIL

 The importance of soil:

T he importance of soil Life , civilization depend on planet's soil and water resources

Future  :

Future Soil will become even more crucial World population doubles every 40 years only 7 percent of earth's surface is suitable for agriculture

Soil is non-renewable resource :

Soil is non-renewable resource T hin, fragile layer of life-supporting material Supplies plants, animals with all resources they need

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How Can We Conserve Soil?

NCSCS Objectives:

NCSCS Objectives Goal 2: The learner will build an understanding of soil concepts. Obj. 2.01 Properties of Soil such as color, texture, and capacity to retain water. Obj. 2.02 Analyze the ability of soil to support the growth of many plants, including those in our food supply. Obj. 2.03 Identify various types of soil: clay, sand, humus

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How Soil Can Be Harmed Plants hold soil in place. When people cut down too many trees and other plants, the water and wind will carry away the soil. If trees are cut down; new ones should be planted to help the soil. with trees after trees are cut down

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Farming on the same land for many years can also be harmful to the soil. The plants will use up all the minerals in the soil. Year after year the minerals are less and less for new plants that are put on the land. The rain forest have thin, poor soil. Plants and crops cannot grow in this soil for long. After the plants are harvested, there is nothing to hold the soil in place. The wind and rain washes it away and cracks are left.

Ways to Save the Soil:

Ways to Save the Soil Another way farmers save the soil is to strip crop. Strip Cropping is planting strips of thick grass or clover between strips of crops. The thick mat helps keep water in the soil and from washing it away.

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Some farmers also use contour plowing. Contour plowing is planting rows of crops around the sides of hills instead of up and down. This way water does not run off in straight lines and the soil isn’t washed away.

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Summary Growing the same type of crop on the same land for many years removes minerals. When people remove plants and tree, soil may be washed away. Farmers conserve soil by strip cropping, contour plowing, and other methods.

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Quiz…

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Question… Use the following information to answer the next question. Laterite soil is formed due to intense leaching owing to heavy rains and is very useful for growing coffee and tea. Laterite soil is most commonly found in A.Maharashtra, Gujarat and Malwa B.Karnataka, Kerala and Tamil Nadu C.Orissa and Chhattisgarh D. Uttar Pradesh, Bihar and West Bengal

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Question… Use the following information to answer the next question. Sheet erosion stands for the removal of the top layer of soil. It is one of the major forms of soil erosion. Which of the following attributes is a major factor for the occurrence of sheet erosion? A. Water B. Wind C. Deforestation D. Wrong ploughing techniques

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Presentation is made by:- Nitish nagar