- Ninety percent of the world population occupies only thirty per cent of land area.
- The remaining seventy percent of the land is either sparsely populated or uninhabited.
- All the economic activities are performed on land.
- The soil cover on the land is essential for plant growth. So land is necessary for agriculture. Land is used to setup industrial units
Lands under Different relief feature
- PLAINS – 43%
- MOUNTAINS – 30%
- PLATEAUS – 27%
- 43% of India’s land area is plain.
Causes of Land Degradation
- Large scale soil erosion caused by running water and wind.
- Dumping of waste materials from mining centers and industrial units.
- Over irrigation leads to increase in salinity and alkalinity in the soil.
- Over grazing by animals and deforestation by man.
- Waste water from the industrial units pollute the lands.
- Mineral processing like grinding of limestone for cement industry and calcite and soap stone for ceramic industry creates a lot of dust.
- This dust is deposited in the neighboring land
Conservation of Land
- Soil erosion can be prevented by ending deforestation, controlling grazing, encouraging afforestation and practicing terrace farming in hilly areas.
- Preparation of shelter belts of plants and stabilizing of sand dunes by growing thorny bushes will help to prevent land degradation in deserts.
- Mining activities should be controlled. New technology which reduces wastage can be adopted.
- Industrial waste should be chemically treated to remove the harmful substances
- Urban waste should be used for the production of biogas and bio-manure.
- Over irrigation should be stopped and new method of irrigation should be followed
Soil Profile and Layers of Soil
Factors Affecting Soil Formation
Types of Soils in India
1. ALLUVIAL SOILS
- Alluvial soil is the most fertile and wide spread soil found in India.
- It is formed due to the deposition of fine silt called alluvium by the rivers.
- It is found in the northern plains, Gujarat plains and the coastal plains
- It consists of sand, silt and clay.
- It is divided into Khadar and Bangar [new alluvium and old alluvium]
- It contains soil nutrients such as Potash, phosphoric acid and lime.
- So, it is fertile and good for the growth of sugarcane, rice, wheat and pulses.
2. BLACK SOILS
- Regur soils are called black cotton soils because they are black in colour and are very good for cotton cultivation.
- It is made up of extremely fine clayey materials.
- It has the capacity to hold moisture for a long time.
- These soils develop deep cracks in summer.
- This helps in the aeration of the soil.
- This soil is sticky.
- It is mainly found in the Deccan Trap region of Maharashtra, Gujarat, Madhya Pradesh and Chattisgarh.
- It is formed due to the weathering of volcanic rocks.
- It is very rich in potash, calcium carbonate, magnesium and lime. It is poor in phosphoric content
3. RED SOILS
- Red soils are formed due to the weathering of crystalline igneous rocks under low rainfall
- It is red in colour because of the presence of iron in it.
- It is found in Tamilnadu, Karnataka, Andhra Pradesh, Orissa, Chattisgarh and Jharkhand.
- The word laterite originated from the Latin word later which means brick.
- Laterite soil is formed due to intense leaching caused by tropical rainfall.
- Humus content is less because the micro-organisms get destroyed due to high temperature.
- This soil can be cultivated by using manure and fertilizers.
- It is good for the cultivation of tea, coffee and cashew nut.
- It is found in Kerala, Karnataka, Tamilnadu, Madhya Pradesh, Orissa and Assam
- Arid soils are red or brown in colour. They are sandy and saline.
- Humus and moisture contents are very less.
- They can be cultivated after irrigation.
- Kankar layer in the soil prevent the water from seeping under ground.
- Forest soils are found in hilly and mountainous regions.
- They are loamy and silty in valleys and coarse in the upper slopes
- In Himalayas they suffer denudation and are acidic with low humus content.
- The soils found in the lower slopes of the valley are fertile.
- Removal of top soil from one place to another by natural agencies is called soil erosion.
- It is caused by running water and wind.
- Deforestation, over grazing and unscientific agricultural practices are responsible for large
scale soil erosion.
- The rain water when moves down on an uneven land scoops away the soil and form deep channels called gullies.
- This type of erosion is called gully erosion.
- A land which is broken into many small parts by the gullies is called bad land.
- A bad land is unfit for cultivation and for other economic activities
- Some times water flows as a sheet over large areas down a slope.
- The water takes away the top soil.
- This type of erosion is called sheet erosion
SOIL CONSERVATION MEASURES
- Contour ploughing reduces the flow of water and prevent soil erosion.
- In hilly areas terraced farming should be followed.
- Strip farming helps to reduces the force of winds.
- Shelter belts of plants around the fields reduce soil erosion.
- Afforestation should be practiced on a large scale and deforestation should be stopped.
- Over grazing by animals should be avoided
Previously Asked Questions
1.Explain resource planning
2. What Steps can be taken to prevent soil erosin in hilly areas
3.what are the main advantages of India’s land under a variety of relief features
4.Mention any three features of arid soil
5.what does the term ‘sustainable economic development’ means ? how can we eradicate irrational consumption and over utilization of resources?