LAND RESOURCES
“A nation that destroys its soils destroys itself.” – Franklin D. Roosevelt
Land as a Resource
Land covers about one-fifth of the Earth’s surface and serves as a fundamental resource for human survival. It provides essential elements such as food, fiber, and fuel for human consumption, fodder for livestock, and raw materials for agro-based industries. The efficient management of land resources is crucial for sustainable agricultural growth and development. Soil, water, vegetation, and climate are the primary natural resources that determine the productivity of land.
Land Degradation
With the rapid increase in population, the demand for arable land is rising to produce food, fiber, and fuelwood. As a result, excessive pressure is being exerted on limited land resources, leading to their degradation. Approximately 56% of India’s total geographical area is affected by land degradation. Key contributors to this issue include:
- Soil erosion
- Waterlogging and salinization
- Industrial waste contamination (e.g., fly-ash, press mud, and heavy metals)
Impact on Canal-Irrigated Areas
Out of 17 million hectares of canal-irrigated land, 3.4 million hectares suffer from waterlogging and salinity, further reducing soil fertility.
Soil Erosion
Soil erosion is the removal or displacement of the topsoil layer due to natural forces like wind, water, and human activities. It results in:
- Loss of fertile topsoil
- Reduced agricultural productivity
- Increased sedimentation in water bodies
Types of Soil Erosion
- Geological Erosion – Occurs naturally over time.
- Accelerated Erosion – Results from human activities such as deforestation, poor farming practices, and overgrazing.
Factors Influencing Soil Erosion
- Soil type
- Vegetation cover
- Slope of the land
- Rainfall intensity
- Human activities
Wind Erosion Mechanisms
- Saltation (bouncing movement of soil particles)
- Suspension (fine particles remain airborne)
- Surface creep (large particles roll along the ground)
Soil Conservation Practices
To mitigate soil erosion and conserve soil, the following methods are recommended:
- Conservation till farming – Reducing soil disturbance to prevent erosion.
- Contour farming and terracing – Cultivating along the natural contours of the land to reduce runoff.
- Strip cropping and alley cropping – Alternating crops in strips to reduce wind and water erosion.
- Windbreaks and shelterbelts – Planting trees to reduce wind speed.
- Terracing – Creating step-like structures to reduce water runoff.
- Shelterbelts – Rows of trees planted to protect crops from strong winds.
- Conservation tillage (USDA, 2007) – Minimizing tillage to preserve soil structure and moisture.
Salinization
Salinization is the accumulation of soluble salts in the soil, which negatively affects crop productivity. This occurs due to:
- Poor drainage – Salt build-up due to water stagnation.
- High temperatures in dry regions – Increases salt concentration.
- Excessive irrigation – Leads to salt deposition on the surface.
Effects of Salinization
- Reduces soil fertility
- Hinders water absorption by plant roots
- Causes physiological drought, even when water is present
Water Logging
Water logging occurs when excessive irrigation disturbs the water balance, leading to a rise in the water table. This results in anaerobic conditions (oxygen deficiency), which affects root respiration and overall plant health.
Consequences of Water Logging
- Root rot due to lack of oxygen
- Reduced soil fertility
- Lower agricultural productivity
Desertification
Desertification is the degradation of productive arid or semi-arid lands, leading to a 10% or more reduction in land productivity. It is characterized by:
- Loss of vegetation
- Groundwater depletion
- Salinization
- Severe soil erosion
Causes of Desertification
- Deforestation – Reduces tree cover, leading to soil degradation.
- Overgrazing – Strips vegetation, exposing soil to erosion.
- Mining and quarrying – Disrupts the natural balance of the land.
Shifting Cultivation (Jhum Cultivation)
Shifting cultivation, also known as slash-and-burn agriculture, is a traditional farming practice used by tribal communities. It involves:
- Clearing forests by burning vegetation.
- Using the land for a short period before moving to a new location.
Negative Effects of Shifting Cultivation
- Deforestation – Leads to biodiversity loss.
- Soil erosion – Reduces land fertility.
- Land degradation – Makes land unproductive over time.
Man-Induced Landslides
Human activities contribute significantly to landslides through:
- Construction of roads, railways, and dams
- Mining and quarrying
- Deforestation
Impact of Landslides
- Destabilizes hill slopes
- Destroys vegetation cover
- Increases soil erosion
CONSERVATION AND EQUITABLE USE OF NATURAL RESOURCES
Role of Individuals in Conservation
Natural resources such as forests, water, soil, minerals, and energy play a vital role in economic development. Individual efforts can significantly contribute to their conservation.
Water Conservation Practices
- Minimize evaporation losses – Irrigate crops in the evening.
- Improve water efficiency – Optimize water usage in appliances.
- Fix leaks – Repair water pipes and taps.
- Recycle water – Use wastewater for gardening.
- Install rainwater harvesting systems.
Energy Conservation Measures
- Turn off electrical appliances when not in use.
- Clean light sources regularly to enhance brightness.
- Utilize renewable energy – Use solar cookers, sun-dry clothes instead of using dryers.
- Limit air conditioning usage to save energy.
Soil Conservation Methods
- Use organic manure and compost.
- Avoid over-irrigation to prevent erosion.
- Adopt sprinkler irrigation to minimize water wastage.
- Increase vegetation cover in gardens and lawns.
Sustainable Agricultural Practices
- Diversify cropping patterns to maintain soil fertility.
- Use fertilizers and pesticides judiciously.
- Improve indigenous livestock breeds for dairy farming.
- Adopt post-harvest technology to reduce food wastage.
Equitable Use of Resources for Sustainable Development
In the last 50 years, resource consumption has increased significantly, leading to inequality between developed and developing nations.
Resource Consumption Statistics
- More Developed Countries (MDCs):
- 22% of the world’s population
- Consume 88% of natural resources
- Use 73% of global energy
- Control 85% of global income
- Less Developed Countries (LDCs):
- 78% of the world’s population
- Use only 12% of natural resources
- Have only 15% of global income
Key Issues
- Overpopulation in poor countries
- Overconsumption by rich countries
Solutions for Sustainable Resource Use
- Reduce consumption in MDCs.
- Implement fair resource distribution policies.
- Encourage global cooperation for balanced natural resource management.
