Classification of resources, land resources, soil types, and soil conservation
Everything available in our environment which can be used to satisfy our needs is a resource. Resources must be technically accessible, economically feasible, and culturally acceptable.
Resources are either natural (air, water, land, forests) or human-made (buildings, roads, technology).
Biotic resources: Derived from living things (plants, animals, fish, humans)
Abiotic resources: Non-living things (rocks, minerals, water, air)
Renewable resources: Can be renewed or reproduced. Solar energy, wind, water, forests (if managed sustainably).
Non-renewable resources: Cannot be renewed once used. Coal, petroleum, natural gas, minerals. Formed over millions of years.
India's total geographical area = 3.28 million sq km
Forest land → ideally should be 33% (currently ~23%)
Net sown area → Land actually cultivated
Fallow land → Left uncultivated temporarily to regain fertility
Barren/Wasteland → Rocky, arid, permanently uncultivable land
Permanent pastures → Grazing land
Causes of land degradation:
• Deforestation, mining and quarrying, overgrazing
• Industrial effluents, chemicals from industries
• Water-logging and soil salinisation from excessive irrigation
Conservation measures: Afforestation, controlled grazing, strip farming, contour bunding, shelterbelts
Soil is formed by weathering — breaking down of rocks by physical, chemical, and biological processes over thousands of years.
Factors: Parent rock, climate (temperature, rainfall), relief (slope), vegetation, time
On an average, 1 cm of soil takes hundreds to thousands of years to form — making it a non-renewable resource on human timescale!
| Soil Type | Colour | State Found | Crops Grown |
|---|---|---|---|
| Alluvial | Light grey to ash | Northern Plains, river valleys, coastal plains | Wheat, rice, sugarcane, cotton, jute — highly fertile! |
| Black (Regur) | Black (high iron, clay) | Deccan Plateau, Maharashtra, MP, Gujarat | Cotton (best for cotton), wheat, sorghum, linseed |
| Red and Yellow | Red (iron content) | Eastern & Southern India, Odisha, Chhattisgarh | Wheat, rice, cotton, tobacco |
| Laterite | Brick red (leached) | Kerala, Tamil Nadu, Assam, Karnataka, MP | Tea, coffee, cashew, rubber (acidic, leached soils) |
| Arid (Desert) | Red to brown | Rajasthan, Gujarat (arid regions) | Drought-resistant crops with irrigation |
| Forest | Variable | Hilly & forested regions | Tea, coffee, tropical fruits |
Sheet erosion: Rainfall washes thin top layer of soil over large area
Rill erosion: Water forms small channels (rills) cutting through soil
Gully erosion: Deep channels cut through soil → "bad land" topography (Chambal ravines)
Wind erosion: Wind blows away topsoil — severe in arid regions (Rajasthan)