Chapter 2: Land, Soil, Water, Natural Vegetation and Wildlife
Land
Land is among the most important natural resources. It covers only about 30% of the total area of the earth’s surface. The uneven distribution of population in different parts of the world is mainly due to varied characteristics of land and climate. Land use is determined by physical factors such as topography, soil, climate, minerals and availability of water, and human factors such as population and technology.
Conservation of Land Resource
Growing population and their ever-growing demand has led to a large scale destruction of forest cover and arable land. Therefore, the present rate of degradation of land must be checked. Afforestation, land reclamation, regulated use of chemical pesticide and fertilisers, and checks on overgrazing are some of the common methods used to conserve land.
Soil
The thin layer of grainy substance covering the surface of the earth is called soil. The right mix of minerals and organic matter makes the soil fertile. Soil erosion and depletion are major threats to soil as a resource. Methods of soil conservation include mulching, contour barriers, terrace farming, intercropping, and shelterbelts.
Water
Water is a vital renewable natural resource. Three-fourths of the earth’s surface is covered with water. However, only a small proportion of it is freshwater that can be used. The main sources of freshwater are rivers, ponds, springs and glaciers. Scarcity of water has become a major problem in many parts of the world. Conservation of water resources is crucial. Methods include rainwater harvesting, using canals for irrigation, and using sprinklers to minimize wastage.
Natural Vegetation and Wildlife
Natural vegetation and wildlife exist only in the narrow zone of contact between the lithosphere, hydrosphere and atmosphere that we call the biosphere. In the biosphere living beings are inter-related and interdependent on each other for survival. This life supporting system is known as the ecosystem.
Conservation of Natural Vegetation and Wildlife
Deforestation, soil erosion, constructional activities, forest fires, tsunami and landslides are some of the human-made and natural factors which accelerate the process of extinction of these resources. To protect our natural vegetation and wildlife, national parks, wildlife sanctuaries and biosphere reserves are made.
Exercise Questions and Answers
1. Answer the following questions.
(i) Which are the two main climatic factors responsible for soil formation?
(ii) Write any two reasons for land degradation today.
(iii) Why is land considered an important resource?
(iv) Name any two steps that government has taken to conserve plants and animals.
(v) Suggest three ways to conserve water.
(i) Which are the two main climatic factors responsible for soil formation?
The two main climatic factors responsible for soil formation are temperature and rainfall. Rainfall contributes to the breaking down of rocks (weathering), and temperature variations cause rocks to expand and contract, leading to cracks and eventual breakdown.
(ii) Write any two reasons for land degradation today.
Two major reasons for land degradation today are:
1. Deforestation: Clearing of forests for agriculture and construction removes the protective vegetation cover, leading to soil erosion.
2. Overuse of chemical fertilisers and pesticides: This degrades the soil quality, reduces its fertility over time, and pollutes the land.
(iii) Why is land considered an important resource?
Land is considered an important resource because it provides the surface for human habitation, agriculture, forestry, setting up industries, and building infrastructure like roads and railways. Essentially, most human activities are based on land.
(iv) Name any two steps that government has taken to conserve plants and animals.
Two steps the government has taken are:
1. Establishing National Parks and Wildlife Sanctuaries: These are protected areas where natural vegetation and wildlife are preserved in their natural habitat.
2. Enacting Laws: Laws like the Wildlife (Protection) Act, 1972, ban the killing and trade of endangered species of animals and birds.
(v) Suggest three ways to conserve water.
Three ways to conserve water are:
1. Rainwater Harvesting: Collecting and storing rainwater for future use.
2. Using Drip or Sprinkler Irrigation: These methods reduce water wastage in agriculture by supplying water directly to the base of the plants.
3. Preventing Water Pollution: Treating industrial and sewage waste before releasing it into water bodies keeps our freshwater sources clean and usable.
2. Tick the correct answer.
(i) Which one of the following is NOT a factor of soil formation?
(a) time (b) soil texture (c) organic matter
(ii) Which one of the following methods is most appropriate to check soil erosion on steep slopes?
(a) shelterbelts (b) mulching (c) terrace cultivation
(iii) Which one of the following is NOT in favour of the conservation of nature?
(a) switch off the bulb when not in use (b) close the tap immediately after using (c) dispose poly-packs after shopping
(i) (b) soil texture
(ii) (c) terrace cultivation
(iii) (c) dispose poly-packs after shopping
3. Match the followings.
(i) Land use (a) prevent soil erosion
(ii) Humus (b) narrow zone of contact between the lithosphere, hydrosphere and atmosphere
(iii) Rock dams (c) productive use of land
(iv) Biosphere (d) organic matter deposited on top soil
(i) Land use - (c) productive use of land
(ii) Humus - (d) organic matter deposited on top soil
(iii) Rock dams - (a) prevent soil erosion
(iv) Biosphere - (b) narrow zone of contact between the lithosphere, hydrosphere and atmosphere
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