Chapter Notes: Land, Soil, Water, Natural Vegetation and Wildlife Resources

Introduction

Nina lives in a Tanzanian village. She fetches water, helps at home and tends goats. Her family struggles to grow enough food on their small, rocky land.

Taylor lives in New Zealand on a sheep farm managed with modern technology. His family runs a wool factory and practises organic farming.

The differences in Nina's and Taylor's lives arise from the availability of natural resources such as land, soil, water and technology. These examples show how resources shape the lifestyle, occupations and development of people in different places.

Observe the land, the type of soil and the water availability in your region and how they influence the lifestyle of people there.

Land

The land is one of the most important natural resources. Roughly 30% of the Earth's surface is land. Land provides space for settlements, farming, industries, forests and infrastructure.

Land

• Ninety per cent of the world's population occupies only 30% of the land area. The remaining 70% of the land is sparsely populated or uninhabited.
• Population distribution on land is uneven because of differences in climate, topography, soil fertility and availability of water.
• Areas that are sparsely populated or uninhabited include rugged mountain slopes, deserts, low-lying flood-prone plains and very thickly forested regions.
• Densely populated regions are usually plains and river valleys that offer suitable land for agriculture and easier access to water and transport.

Land Use

Land use means the way land is used for different purposes such as agriculture, forestry, mining, housing, roads and industries. Land use patterns change with economic development and cultural practices.

Land use is influenced by two main types of factors:

1. Physical factors: topography, soil quality, climate and availability of water determine which uses are possible on a piece of land.
2. Human factors: population pressure, technology, economic activities and social organisation influence how land is put to use.

On the basis of ownership, land can be classified as:

• Private land - owned by an individual, family or private organisation and used for personal or commercial purposes (for example, a house plot or private farm).
• Community land - owned by the community and used for common purposes such as grazing, collection of fodder, non-timber forest products, fruits and medicinal herbs. Such lands are also called common property resources.

Challenges in Land Use

• Demand for land increases with population growth, but the total land area is limited.
• Large changes in land use patterns reflect economic and cultural changes in society.
• Major threats to land include land degradation, soil erosion, landslides and desertification, often caused by deforestation, careless agricultural practices and unregulated construction.

Land Habitation

Conservation of Land Resources

• Increasing population and higher demands have caused large-scale loss of forest cover and reduction in arable land. The current rate of land degradation needs to be checked.
• Common methods to conserve land resources include afforestation, land reclamation, regulated use of chemical fertilisers and pesticides, and controls on overgrazing.
• Soil and water conservation measures, community-based management of common property resources, and improved agricultural practices help sustain land productivity.

Soil

Soil is a thin, loose layer of material that covers the Earth's surface. It is made up of organic matter (decayed plants and animals), minerals, weathered rock particles and living organisms.

Soil profile describes the vertical arrangement of soil layers from the surface down to the parent rock. The profile helps us understand soil fertility, texture and drainage.

 Soil

1. Topsoil (surface layer) - rich in humus and nutrients and supports vegetation.
2. Subsoil - contains sand, silt and clay with fewer organic materials than topsoil.
3. Weathered rock material - partially broken and chemical altered rock fragments.
4. Parent rock - the unweathered solid rock from which the soil develops.

Layers of soil:- Soil Profile

Glossary: Weathering

Weathering - the breaking up and decay of exposed rocks by temperature changes, frost action, plants, animals and human activity. Weathering is the first step in soil formation.

Landslides

Landslides are the downward movement of rock, debris or earth on a slope. They often occur after heavy rain, earthquakes or volcanic activity. Extended rainfall can trigger landslides, block rivers and damage areas downstream when such natural dams burst.

In hilly regions, landslides are a frequent and serious natural hazard, threatening life, settlements, roads and other infrastructure.

Landslide

Case Study

A massive landslide struck Pangi village near Reckong Peo in Kinnaur district, Himachal Pradesh, damaging a 200-metre section of the old Hindustan-Tibet road (National Highway 22). The landslide was triggered by intense blasting in the area, which caused an unstable slope to collapse. The road and nearby villages suffered severe damage and the entire Pangi village was evacuated as a precaution.

Mitigation Measures for Landslides

Scientific techniques help identify landslide-prone areas and suggest measures to reduce risk. Key measures include:

• Hazard mapping - identifying areas prone to landslides so settlements and infrastructure can be planned away from them.
• Retention walls - structures built to hold soil in place and prevent sliding.
• Vegetation cover - planting and maintaining trees and grasses to bind soil and reduce slope instability.
• Surface drainage control - building drains, channels and trenches to control rainwater and spring flow and reduce saturation of slopes.

Factors of Soil Formation

The major factors that affect how soil forms are the nature of the parent rock, climate, topography, biological activity and time. Each factor influences soil properties such as texture, colour, depth and fertility.

1. Parent rock - determines the mineral composition, texture and permeability of the soil.
2. Relief (topography) - slope and altitude affect the accumulation and movement of soil materials.
3. Flora, fauna and micro-organisms - plants and animals add organic matter (humus) and help mix the soil.
4. Climate - temperature and rainfall affect the rate of weathering and organic decomposition; warm, moist climates speed up soil formation.
5. Time - it takes hundreds of years to form a few centimetres of soil; the thickness and maturity of a soil profile increase with time.

Degradation of Soil and Conservation Measures

Soil erosion and nutrient depletion threaten soil as a natural resource. Both human activities and natural processes contribute to soil degradation. Major causes include deforestation, overgrazing, excessive use of chemical fertilisers and pesticides, improper irrigation, landslides and floods.

Methods for soil conservation:

1. Mulching - covering bare soil around plants with organic material (straw, leaves) to retain moisture and reduce erosion.
2. Contour barriers - building stone, grass or earth barriers along contours to slow water flow and trap soil; trenches along contours help collect water.
3. Rock dams - piling rocks across gullies to slow the speed of water and prevent gully erosion.
4. Terrace farming - creating wide, flat steps on steep slopes to reduce runoff and provide stable areas for crops.
   
5. Intercropping - growing different crops together so plant cover is continuous and soil is protected from rain wash.
6. Contour ploughing - ploughing along the natural contours of slopes to reduce the velocity of surface runoff.
7. Shelter belts - planting rows of trees in dry and coastal regions to reduce wind speed and protect soil from wind erosion.
   

   Shelter Belts

Water

Water is a vital renewable natural resource. Around three-fourths of the Earth's surface is covered by water, which is why Earth is sometimes called a "water planet." Most of this water is saline and found in the oceans; only a small fraction is fresh and usable.

• About 2.7% of the Earth's water is fresh water (frozen polar ice and freshwater combined). Of this, only roughly 1% of the Earth's total water is easily accessible fresh water found in rivers, lakes and shallow groundwater.
• Water is conserved in a continuous cycle through evaporation, condensation and precipitation. This movement is known as the water cycle.
• Water is essential for agriculture, industry, domestic use and for generating electricity through reservoirs and dams.
• The major causes of water shortage are increasing population, rising demand for food and cash crops, urbanisation and higher standards of living.

• The visible abundance of water varies regionally because water continuously cycles between the oceans, atmosphere and land through evaporation, precipitation and runoff.
• Water is used for irrigation, industrial processes, drinking, sanitation and generation of hydroelectricity.

Source of Water

Problems of Water Availability

• Many regions face water shortage because of low or uneven rainfall, over-exploitation of groundwater and contamination of water sources.
• Regions most susceptible to droughts and severe water scarcity include parts of Africa, West Asia, South Asia, parts of the western United States, north-west Mexico, parts of South America and much of Australia.

Conservation of Water Resources

Although water is renewable, overuse and pollution make much of it unusable. Conserving water and improving its quality are essential.

• Pollution from sewage, agricultural chemicals and industrial waste adds nitrates, heavy metals and pesticides to water bodies.
• Forest and vegetation cover slow surface runoff and allow more water to percolate into the ground, recharging groundwater reserves.
• Water harvesting methods (catching surface runoff) and rainwater harvesting (collecting rain from roofs into storage) help save water for future use.
• Irrigation canals should be checked for seepage and evaporation losses.
• Sprinkler irrigation spreads water like rain and reduces losses compared to flood irrigation. Drip (trickle) irrigation supplies water directly to the roots and is very efficient in dry regions with high evaporation rates.
• Other measures include watershed management, check dams and lining canals to reduce seepage.

Natural Vegetation and Wildlife

Natural vegetation and wildlife occur within the biosphere - the narrow zone where the lithosphere (land), hydrosphere (water) and atmosphere meet and support life.

Tiger

Within the biosphere, living organisms form an interdependent system called the ecosystem. Plants and animals rely on each other and on physical factors such as soil, water and climate.

• Plants provide timber, fuel, shade and habitat for animals, produce oxygen and help retain soil and store underground water. They also act as shelterbelts along coasts and fields.
• Wildlife includes animals, birds, insects and aquatic life. They supply milk, meat, hides and wool, help in pollination and seed dispersal, and act as decomposers that recycle nutrients back into the soil.

A Bird

Distribution of Natural Vegetation

Vegetation growth depends mainly on temperature and moisture. The major types of natural vegetation are forests, grasslands, scrubs and thorny vegetation, and tundra.

1. Forests occur where water supply is abundant. These areas receive heavy rainfall and support tall, dense trees.
2. Grasslands have grasses and scattered short trees and grow where rainfall is moderate.
3. Thorny shrubs and scrubs dominate dry areas with low rainfall. Plants here have deep roots and waxy or thorny leaves to reduce water loss by transpiration.
4. Tundra vegetation in cold polar regions consists mainly of mosses, lichens and small shrubs adapted to very low temperatures.
5. Evergreen forests do not shed all their leaves at the same time and remain green throughout the year; deciduous forests shed their leaves seasonally (usually in the dry season) to conserve moisture.

Types of Natural Vegetation

Conservation of Natural Vegetation and Wildlife

Forests are vital as they provide habitat for wildlife, protect soil and water resources, and support biodiversity and local livelihoods.

Threats to Biodiversity

1. Climate change - alters habitats and affects the survival of plant and animal species.
2. Human activities - deforestation, soil erosion, urbanisation, construction and forest fires destroy habitats.
3. Natural disasters - tsunamis, landslides and floods can remove or damage habitats.
4. Poaching - illegal hunting for hides, skins, horns and other body parts threatens species such as tigers, rhinos and elephants.

Conservation Efforts

1. Protected areas - national parks, wildlife sanctuaries and biosphere reserves protect important habitats and species.
2. Legal protection - laws forbid hunting, capture and trade of endangered species (for example, protection of tigers, lions and peacocks in India).
3. International agreements - CITES (Convention on International Trade in Endangered Species) regulates international trade in species that might be threatened by trade.

Public Awareness and Education

1. Programs such as social forestry, Vanamahotsav (tree planting festival) and nature camps educate people about the importance of trees and wildlife.
2. School initiatives encourage students to take part in bird watching, tree planting and nature exploration to understand local biodiversity.
3. Ethical responsibility - conserving biodiversity is a shared duty. Protection of plants and animals keeps ecosystems balanced and ensures resources for future generations.

Glossary

National Park - a natural area designated to protect the ecological integrity of one or more ecosystems for present and future generations.

Biosphere reserve - a protected area (often containing a core protected area, buffer zone and transition zone) that demonstrates a balanced relationship between conservation and sustainable use; biosphere reserves are linked through a global network.

CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora) - an international agreement between governments that aims to ensure international trade in wild animals and plants does not threaten their survival. Approximately 5,000 animal species and 28,000 plant species are listed for protection under CITES; examples include certain bears, dolphins, corals, orchids and aloes.

Summary: Land, soil, water, natural vegetation and wildlife are interconnected resources that determine livelihoods and development. Their sustainable use and careful conservation-through afforestation, soil and water conservation practices, protected areas, legal frameworks and public education-are essential to maintain ecological balance and ensure resources for future generations.