Chapter 2 – Land, Soil, Water, Natural Vegetation and Wildlife Resources
- Land Resources
- Land is the most important natural resource. Only about 30% of the Earth’s surface is land, and not all parts of even this small percentage are habitable.
- The uneven distribution of population is mainly due to different features of land and climate.
- Densely populated areas: plains and valleys of rivers (fertile land, availability of water).
- Sparsely populated areas: mountainous terrain, marshlands, deserts, dense forests.
- Land Use :
- Land is used for various purposes, such as agriculture, forestry, mining, roads and making factories.
- Land use is determined by physical factors (topography, soil, climate, mineral and water availability) and human factors (population and technology).
- Ownership of Land:
- Private Land: Owned by individuals.
- Community Land: Owned by the community (e.g. pastures, fruits, medicinal herbs). They are also called common property resources.
- Conservation of Land Resource:
- Due to the increasing population and their increasing demands, there is a large-scale destruction of land and arable land.
- Methods: Afforestation, land reclamation, regulating the use of chemical pesticides and fertilizers, control over overgrazing.
- Soil Resource
- Soil is the thin layer of granular matter on the surface of the earth.
- It is land-intensive.
- Soil Formation:
- Soil is formed by the breakdown of rocks (weathering).
- This process takes millions of years.
- Factors of Soil Formation:
- Parent Rock: Determines soil color, texture, chemical properties, mineral content, and permeability.
- Climate : Temperature, rainfall, weathering, and humus affect the rate of build-up.
- Topography: Elevation and slope determine the accumulation of soil.
- Time: Determines the thickness of the soil profile.
- Flora, Fauna, and Micro-organisms: Affect the rate of humus formation.
- Soil Degradation and Conservation Measures:
- Soil degradation and erosion are the major threats.
- Causes: Deforestation, encroachment, excessive use of chemical fertilizers and pesticides, rain wash, landslides, floods.
- Conservation Methods:
- Mulching: Covering the vacant ground between plants with a layer of organic matter (such as straw). It maintains the moisture content of the soil.
- Terrace Farming: Creating flat surfaces (stairs) on steep slopes so that soil erosion is reduced.
- Contour Ploughing: Ploughing parallel to the contour lines on a hill slope so that the flow of water from the slope is slow.
- Shelter Belts: Planting rows of trees to prevent wind movement in coastal areas and arid regions.
- Contour Barriers: Creating barriers using stones, grass, and soil on contour lines.
- Rock dams: Stacking rocks to slow down the flow of water. It prevents soil erosion.
- Intercropping: Growing different crops in alternate rows so as to prevent soil deception from rain.
- Water Resources
- Water is an important renewable natural resource.
- Three-fourths of the earth is covered with water. That’s why it is also called the Water Planet.
- However, only 2.7% of the total water available on earth is fresh water.
- About 70% of this freshwater is in the form of ice sheets and glaciers, which are inaccessible.
- Therefore, the availability of freshwater is very low.
- Freshwater sources: Rivers, lakes, ponds, and groundwater.
- Problems of Water Availability:
- There is a shortage of water in many parts of the world.
- This may be due to variation or over-exploitation in seasonal or annual rainfall across climatic zones.
- Conservation of Water Resource:
- Water is a renewable resource, but its excessive use and pollution can make it unusable.
- Causes: Unrefined sewage, agricultural chemicals (pesticides, fertilizers), industrial wastes pollute the water.
- Methods:
- Maintaining vegetative cover (to slow down surface runoff).
- Preventing industrial effluents from being discharged into water bodies without being treated.
- Promoting Rainwater Harvesting.
- Lining the canals properly so that water leakage is reduced.
- Using efficient methods such as drip irrigation and sprinklers to irrigate the fields.
- Natural Vegetation and Wildlife Resources
- Natural vegetation and wildlife exist only in the biosphere. The biosphere is a narrow area of land, water, and air where life exists.
- Ecosystem: All living organisms in the biosphere depend on each other and on their environment, forming an ecosystem.
- Uses :
- Flora: wood, fruits, nuts, latex, turpentine oil, gum, medicinal plants, paper.
- Wildlife: Milk, meat, skins, wool (animals), bee pollination, decomposition.
- Distribution of Natural Vegetation:
- The growth of vegetation depends mainly on temperature and moisture.
- Forests : In areas with sufficient rainfall.
- Evergreen Forests: Always green.
- Deciduous Forests: shed their leaves in the dry season.
- Grasslands: In areas with moderate rainfall.
- Shrubs: In arid regions.
- Tundra Vegetation: Mosses and lichens in the polar regions.
- Conservation of Natural Vegetation and Wildlife:
- It is necessary to maintain a balance of vegetation and wildlife.
- Endangered Species: Many species are endangered or on the verge of extinction (such as tigers).
- Hazard Causes: Deforestation, soil erosion, construction work, forest fires, tsunamis, landslides, poaching.
- Conservation Methods:
- Establishing National Parks, Wildlife Sanctuaries and Biosphere Reserves.
- Conservation of Biodiversity: Regulating Human Activities.
- Conservation of Lakes and Wetlands: These are important habitats.
- Banning hunting .
- Awareness Programmes: Such as Van Mahotsav.
- International Agreements: Such as CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) which regulates the international trade of animals and plants.