Maarg Manthan · Topic 10.15

Changes in Land Use and Land Cover

Geography › Urbanization, Settlements and Migration · Topic 10.15

Land use is the way people use land, such as farming, housing, industry or forestry, while land cover is the physical material on the surface, such as crops, trees, water, bare soil or built-up area. Land-use and land-cover change (LULC) is studied by remote sensing and geographic information systems. Major changes are the conversion of farmland and forest to built-up area, expansion of cropland, loss of wetlands and forests, and growth of irrigation. These changes affect climate, water, biodiversity and food, and create effects like the urban heat island.

5 min read · UPSC Prelims · Geography · Urbanization, Settlements and Migration

At a Glance

Land use How land is used by people
Land cover What covers the surface
Tools Satellites and GIS
Main drivers Urban growth, farming, deforestation
Impact Climate, water, biodiversity
Exam link UPSC Prelims, Geography: Urbanization, Settlements and Migration

Where Does It Fit?

This topic closes the macro on settlements and urbanisation by looking at what happens to the land as cities and farms spread. It leads to the macro on agriculture, which starts with land use and land capability. Previous topic: Principles of Urban Planning. Next topic: Classification of Cities: Hierarchical and Morphological.

What Are Land Use and Land Cover and How Are They Mapped?

Term	Meaning	Example
Land use	The purpose for which people use the land	Farming, housing, industry, pasture, recreation
Land cover	The physical or biological cover of the earth’s surface	Forest, grass, crops, water, bare rock, concrete
Land-use change	Change in the purpose	Farmland converted into a housing colony
Land-cover change	Change in the cover	Forest turned into scrub

Remote sensing: satellites such as the Indian Resourcesat and Landsat photograph the earth in different wavelengths, and a computer sorts the pixels into classes.
India: the National Remote Sensing Centre of ISRO has made national land use and land cover maps for 2005-06, 2011-12 and later periods, using a standard classification, and the Bhuvan portal shows them.
Land use statistics: revenue records give a nine-fold classification of reporting area (forest, non-agricultural uses, barren land, permanent pastures, tree crops, culturable waste, fallow lands, current fallow and net sown area), described in the macro on agriculture.

What Are the Drivers of Change?

Urban expansion: the built-up area of Indian cities has grown faster than their population, taking in farmland on the fringe, as seen in the spread of Delhi, Bengaluru, Pune and Hyderabad.
Agricultural intensification and expansion: clearing of forests and grasslands for crops, and spread of irrigation, orchards and aquaculture ponds.
Deforestation and degradation: described in Deforestation: Tropical and Temperate Forest Loss and Conservation Issues Relating to Indian Natural Vegetation.
Mining, roads and industry: open-cast mines, highways and special economic zones convert large areas.
Loss of wetlands and water bodies: lakes and marshes filled for housing and roads.
Policy and markets: land prices, subsidies and zoning decisions.
Climate and natural change: drought, floods, fires and sea level rise change land cover.

What Are the Impacts?

Urban heat island: built-up surfaces such as concrete and asphalt absorb heat and replace cooling vegetation, so cities are several degrees warmer than the surrounding countryside, especially at night.
Hydrology: sealed surfaces increase runoff and floods and reduce groundwater recharge, as in Urban Infrastructure Challenges: Urban Transport, Waste Disposal, Water Supply, Drainage, Sanitation.
Climate: forest loss releases carbon and changes surface albedo and moisture.
Biodiversity: habitat loss and fragmentation.
Food security: loss of good farmland to housing. India loses a large area of fertile land around cities every year.
Soil and water quality: erosion, salinity and pollution.

Planning tools to manage these changes are discussed in Principles of Urban Planning, and the sustainable use of land in Sustainable Land Management. Change can be measured in several ways: by the area converted from one class to another (a transition matrix), by the rate of change per year, and by the pattern, such as fragmentation or scattering. In India the area under built-up use is small, only a few per cent of the land, but it is growing fast, and it consumes the best farmland, because cities grew in the fertile plains. Forest cover has been stable in area according to the national forest survey, while the area under tree crops and plantation has gone up and the area of wetlands has fallen. The data also help courts and agencies in cases about encroachment on lakes, floodplains and forest land. As an analytical point, land cover change is the most visible sign of human pressure on the planet, and monitoring it from space allows early warning of problems and checking of policies such as afforestation targets.

Why Is This Topic Important?

Concept Use versus cover
Method Remote sensing
Link Urban heat island

What Came Next?

The next topic covers the classification of cities: hierarchical and morphological. Next topic: Classification of Cities: Hierarchical and Morphological.

Key People and Terms

LULC Land use and land cover
Remote sensing Observing the earth from satellites
GIS Geographic information system
Urban heat island City warmer than its surroundings
Built-up area Land covered by buildings and roads
Pixel Unit of a satellite image

Exam Corner

Points to Remember

Land use is purpose; land cover is surface.
NRSC maps land use and cover for India.
Urban areas form a heat island.
Sealed surfaces raise runoff.
Bhuvan is ISRO’s geoportal.

Do Not Confuse With

Land use and land cover Human purpose versus physical surface
Land-use change and degradation Change of purpose versus decline in quality
Urban heat island and global warming Local city warmth versus planet-wide warming

Memory Hook

Use is the why, cover is the what; satellites watch the fields turn to plot.

Mains Angle

Questions ask about the drivers and impacts of land-use change. These points add depth.

Drivers Urban and farm expansion
Impacts Heat, water, species, food
Tools Satellite monitoring and planning

A Question You May Face

An original practice question, not a past paper question.

“Discuss the causes and impacts of land-use and land-cover change in India, and explain how remote sensing helps in monitoring them.”

How to Answer

Define Land use and cover.
Drivers Urban, farm, mining.
Impacts Heat, floods, species.
Monitoring Satellite maps.

GS Relevance

Prelims: land use versus land cover, remote sensing, drivers and impacts. GS Paper 1 and 3: land resources, urbanisation, environment.

Frequently Asked Questions

What is the difference between land use and land cover?

Land use is the way people use land, such as for farming, housing, industry or recreation. Land cover is the physical material on the surface, such as forest, grass, crops, water or buildings. A single land cover, such as grass, may have many uses, like grazing or a park.

How is land-use change studied?

Land-use and land-cover change is studied with satellite remote sensing and geographic information systems. Images from different dates are classified into classes such as crops, forest, water and built-up land, and compared. In India the National Remote Sensing Centre of ISRO prepares national land use and land cover maps.

What are the main causes of land-use change in India?

The main causes are the growth of cities onto farmland, expansion and intensification of agriculture, deforestation, mining, new roads and industrial areas, loss of wetlands, and aquaculture. Government policies on land, subsidies and zoning, as well as population growth and rising incomes, also influence the change.

What is the urban heat island effect?

The urban heat island effect is the higher temperature of a built-up area compared to its surrounding countryside, caused by dark surfaces such as asphalt and concrete that absorb and hold heat, loss of vegetation, and heat from vehicles and air conditioners. It is strongest at night and increases energy use and health risks.

Why does loss of wetlands matter?

Wetlands store flood water, recharge groundwater, filter pollutants and shelter birds and fish. When they are filled for roads and housing, cities lose their natural flood protection, so heavy rain leads to floods, as in Chennai in 2015, and biodiversity and water quality decline.

PYQ Practice — Statement Analysis

1 Land cover refers to the human use of the land.

False

That is land use; cover is the surface.

2 Remote sensing helps to monitor changes in land cover.

True

Satellite images are compared over time.

3 Urban areas are generally cooler than the surrounding countryside.