NCERT Summary: Land, Soil, Water, Natural Vegetation and Wildlife | Geography for UPSC CSE PDF Download

Introduction

Natural Resources encompass resources derived from nature like land, water, and air.

Land

• One of the most important natural resources
• Covers about thirty percent of the total area of the earth’s surface, however all parts are not habitable.
• The reason behind uneven distribution of population in different parts of the world is mainly due to varied characteristics of land and climate.
• Areas which are normally sparsely populated or uninhabited: rugged topography, steep slopes of the mountains, low-lying areas susceptible to water logging, desert areas, thick forested areas. 

Land Use

• The different purpose such as agriculture, forestry, mining, building houses, roads and setting up of industries for which land is used is known as land Use.

• The factors that determine use of land are:
  → Topography
  → Soil
  → Climate
  → Minerals
  → Availability of water
• Important determinants of land use pattern:
  → Human factors such as population
  → Technology
•  Land Division on the basis of private land and community land:
  → Private land is owned by individuals
  → Community land is owned by the community for common uses like collection of fodder, fruits, nuts or medicinal herbs. Also called common property resources. 
• Population and demands are increasing but land is limited. Many constructional activities are going on also agricultural land is expanding. These are leading to land degradation, landslides, soil erosion, desertification which are major threats to the environment. 

Private vs. Community Land

• Private Land: Owned by individuals
• Community Land: Owned collectively for communal uses like foraging, fruit picking, or medicinal plant collection

Conservation of Land Resources

• Causes of degradation of land resources: The extensive destruction of forest cover and fertile land due to increasing demands.
• Methods to monitor the current rate of land resource degradation:
  • Afforestation
  • Land reclamation
  • Regulated use of chemical pesticides and fertilizers
  • Control measures on overgrazing

Soil

• Definition: Soil refers to the thin layer of granular material covering the Earth's surface.
• Composition of soil: It consists of organic matter, minerals, and weathered rocks present on Earth. The type of soil is determined by the landforms in the area.

• Factors influencing soil formation:
  • Nature of the parent rock
  • Climate
  • Topography
  • Role of organic material
  • Time

Degradation of Soil

• Major threats to soil as a resource: Soil erosion and depletion.
• Causes of soil degradation:
  • Deforestation
  • Overgrazing
  • Excessive use of chemical fertilizers or pesticides
  • Rain wash
  • Landslides
  • Floods

Soil Conservation

• Mulching: Applying a layer of organic material like straw on the uncovered ground between plants to preserve moisture and reduce erosion.

• Contour barriers: Stones, grass, soil are used to build barriers along contours. Trenches are made in front of the barriers to collect water.
• Rock dam: Rocks are piled up to slow down the flow of water, preventing gullies and soil loss.
• Terrace farming: Developing terraces on steep slopes to reduce surface run-off and soil erosion.
• Intercropping: Growing different crops in alternate rows at different times to protect the soil from rain wash.
• Contour ploughing: Ploughing parallel to hill slope contours to form a natural barrier for water flow.
• Shelter belts: Planting rows of trees in coastal and dry regions to check wind movement and protect soil cover.

Water

• Water is an essential and renewable resource on Earth.
• Three-fourths of Earth's surface is covered with water, earning it the name 'water planet'.
• Oceans cover two-thirds of the Earth's surface, but their water is saline and not suitable for human consumption.
• Freshwater accounts for only about 27 percent, with most inaccessible in ice sheets, glaciers, and mountain regions.
• Only 1 percent of freshwater is available and suitable for human use, found as groundwater, surface water in rivers and lakes, and water vapor in the atmosphere.
• Freshwater is incredibly precious as it cannot be added or subtracted from the Earth.

Water Resources

• An abundance of water appears to fluctuate due to its continuous movement in the Water Cycle. This cycle involves the circulation of water through oceans, the atmosphere, the land, and back again via processes such as evaporation, precipitation, and run-off.
• Human usage of water extends beyond drinking and washing to include agricultural practices, industrial operations, and the generation of electricity through dam reservoirs.
• Factors contributing to shortages in the availability of fresh water include:
  • Increasing population
  • Rising demands for food and cash crops
  • Growing urbanization
  • Elevating standards of living
• These factors often lead to the depletion of water sources or contamination, resulting in water scarcity or pollution.

Problems of Water Availability

• Regions experiencing shortages in fresh water supply include most of Africa, West Asia, South Asia, parts of western USA, north-west Mexico, parts of South America, and the entirety of Australia.
• Water scarcity may arise from fluctuations in seasonal or annual precipitation or from over-exploitation and pollution of water sources.

Conservation of Water Resources

• Primary contaminants affecting water bodies include untreated or partially treated sewage, agricultural chemicals, and industrial effluents.
• Methods to mitigate water pollution involve:
  • Utilization of forests and vegetation to reduce surface runoff and replenish groundwater.
  • Implementation of water harvesting techniques to conserve surface runoff.
  • Lining canals effectively to minimize water seepage losses.
  • Efficient use of sprinklers to irrigate areas, thus reducing water losses through seepage and evaporation.

Natural Vegetation and Wildlife

• The biosphere refers to the interface where natural vegetation and wildlife coexist, involving the lithosphere, hydrosphere, and atmosphere.

• An ecosystem denotes the intricate web of relationships between organisms and their environment within a specific area.
• Plants serve various purposes:
  • They offer timber for construction.
  • Plants provide shelter to animals.
  • They are the primary source of oxygen essential for life.
  • Plants help in soil conservation, crucial for agriculture.
  • Act as shelter belts, protecting from natural elements.
  • Contribute to the storage of underground water.
  • Supply fruits, nuts, latex, medicinal plants, and materials like paper.
• Wildlife encompasses animals, birds, insects, and aquatic life forms, offering benefits such as:
  • Provision of milk, meat, hides, and wool.
  • Pollination of flowers by insects like bees.
  • Decomposition of organic matter by birds and insects, enriching the ecosystem.
• Vultures, acting as scavengers by feeding on dead animals, play a crucial role in maintaining environmental cleanliness.

Distribution of Natural Vegetation

• Vegetation distribution is primarily influenced by temperature and moisture levels in an area.
• Key vegetation types worldwide include:
  • Forests
  • Grasslands
  • Scrubs
  • Tundra
• Forests thrive in regions with abundant rainfall, leading to the growth of large trees.
• With decreasing moisture, tree size and density reduce, eventually giving rise to short trees and grasslands in moderately rainy areas.
• In arid regions with low rainfall, you find thorny shrubs and scrubs. These plants have deep roots and leaves with thorny and waxy surfaces to minimize moisture loss through transpiration.

• The tundra vegetation in cold Polar Regions consists mainly of mosses and lichens.
• Forests can be classified based on when they shed their leaves:
  • Evergreen forests retain their leaves throughout the year without simultaneous shedding.
  • Deciduous forests shed their leaves in a particular season to reduce moisture loss through transpiration.
• Deciduous forests are further categorized based on their location in various latitudes, including Tropical and Temperate regions.
• Global forest cover is rapidly diminishing.

Conservation of Natural Vegetation and Wildlife

• Plants provide shelter to animals, contributing to the maintenance of ecosystems.
• Climate changes and human interventions can lead to the loss of natural habitats for plants and animals.
• Various species are at risk of extinction due to natural and human-induced factors such as deforestation, soil erosion, construction activities, forest fires, tsunamis, and landslides.
• Poaching activities are on the rise, resulting in a significant decline in the populations of certain species. Animals are poached for items like hides, skins, nails, teeth, horns, and feathers.
• Some examples of poached animals include tigers, lions, elephants, deer, blackbucks, crocodiles, rhinoceroses, snow leopards, ostriches, and peacocks.