Overview

Soil is the foundation of terrestrial life -- supporting agriculture, regulating water cycles, storing carbon, and hosting immense biodiversity. Yet soil degradation affects approximately 96.4 million hectares (~29.3% of India's total geographical area) according to ISRO/Space Applications Centre data. Globally, the United Nations estimates that up to 40% of the world's land is degraded. Desertification -- the degradation of land in arid, semi-arid, and dry sub-humid areas -- threatens food security, livelihoods, and biodiversity across continents.

For UPSC, soil degradation connects GS3 (Environment, Agriculture) and GS1 (Geography) -- questions test understanding of degradation types, India's soil health schemes, the UNCCD framework, Land Degradation Neutrality targets, and the interplay between land use change, agriculture, and climate.

Types of Soil Degradation

Type Description Key Causes Affected Regions in India
Water erosion Removal of topsoil by flowing water (sheet, rill, and gully erosion) Deforestation, overgrazing, sloping terrain without terracing, heavy rainfall Shivalik hills, Chambal ravines, Western Ghats, northeastern states
Wind erosion Removal and transport of soil particles by wind Lack of vegetation cover, sandy soils, dry climate Rajasthan (Thar Desert), Gujarat, parts of Haryana and Punjab
Salinisation Accumulation of soluble salts (NaCl, Na2SO4) in the root zone, rendering soil unfit for cultivation Poor drainage, excessive irrigation (waterlogging leads to capillary rise of saline groundwater), canal irrigation without adequate drainage Indo-Gangetic plains (especially Punjab, Haryana, UP), Gujarat, Rajasthan
Waterlogging Saturation of soil with water, leading to oxygen-depleted (anaerobic) conditions in the root zone Over-irrigation, poor drainage infrastructure, canal seepage Punjab, Haryana (canal-irrigated areas), coastal areas
Acidification Decrease in soil pH, reducing nutrient availability and increasing toxic aluminium Excessive use of ammonium-based fertilisers, acid rain, leaching of basic cations Northeastern states, Kerala, parts of Western Ghats (high rainfall areas)
Nutrient depletion Loss of essential nutrients (N, P, K, micronutrients) faster than they are replenished Intensive monoculture, inadequate fertiliser use, removal of crop residues, lack of organic matter replenishment Widespread across India; particularly severe in states practising rice-wheat monoculture
Compaction Compression of soil particles, reducing porosity and infiltration Heavy machinery, livestock trampling, repeated tillage at the same depth Mechanised farming regions (Punjab, Haryana, MP)
Contamination Introduction of pollutants (heavy metals, pesticides, industrial waste) into soil Industrial effluents, mining waste, excessive pesticide/herbicide use, improper waste disposal Industrial belts (Vapi in Gujarat, Ludhiana in Punjab, mining areas in Jharkhand, Odisha)

Causes of Soil Degradation

Natural Causes

Cause Detail
Climate variability Droughts reduce vegetation cover, exposing soil to erosion; intense rainfall events cause sheet and gully erosion
Topography Steep slopes accelerate water erosion; flat terrain in arid areas is susceptible to wind erosion
Geological factors Parent rock composition affects soil vulnerability; soils derived from soft sedimentary rocks erode more easily

Anthropogenic Causes

Cause Detail
Deforestation Removal of forest cover eliminates the root network that binds soil, the canopy that breaks rainfall impact, and the leaf litter that replenishes organic matter
Overgrazing Livestock consume vegetation faster than it can regenerate, leaving soil exposed; compaction by hooves reduces infiltration
Unsustainable agriculture Monoculture, excessive chemical fertilisers, burning of crop residues, absence of crop rotation, and over-irrigation
Mining Open-cast mining removes topsoil entirely; mine waste (overburden, tailings) contaminates surrounding land and water
Urbanisation Conversion of agricultural and forest land to built-up areas; soil sealing by concrete and asphalt
Climate change Shifts in precipitation patterns, increased frequency of extreme events (droughts, floods), higher temperatures accelerating decomposition of soil organic matter

For Mains: Soil degradation in India is both a cause and consequence of rural poverty. Degraded soils reduce agricultural productivity, pushing farmers to cultivate marginal lands (further degradation) or migrate to cities (urbanisation pressure). Breaking this cycle requires integrated approaches -- soil health management, watershed development, agroforestry, and livelihood diversification.

Extent of Soil Degradation in India

ISRO/SAC Assessment

Parameter Data
Source Desertification and Land Degradation Atlas of India (ISRO/Space Applications Centre, Ahmedabad)
Assessment year 2011--2013 data (published 2016)
Total degraded area 96.4 million hectares (~29.3% of India's total geographical area of 328.7 Mha)
Most degraded states Rajasthan (21.53 Mha), Maharashtra (13.83 Mha), Gujarat (8.89 Mha), erstwhile J&K (7.66 Mha), Karnataka (7.38 Mha) -- these 5 states account for ~two-thirds of India's total degraded land
Change (2003--2013) Degraded area increased from 94.53 Mha to 96.40 Mha (~2 Mha increase in a decade)
Dominant process Water erosion is the single largest contributor, followed by vegetation degradation and wind erosion

India's Degraded Land by Process

Process Area (approximate)
Water erosion ~37% of degraded area
Vegetation degradation ~25%
Wind erosion ~19%
Salinisation / Alkalinisation ~6%
Waterlogging ~4%
Others (mining, urbanisation, frost) ~9%

Desertification and UNCCD

What Is Desertification?

Feature Detail
Definition Land degradation in arid, semi-arid, and dry sub-humid areas resulting from various factors including climatic variations and human activities (UNCCD definition)
Not the same as Desert expansion -- desertification can occur far from existing deserts; it is about loss of biological productivity of land
Global scale Up to 40% of the world's land is degraded, affecting ~3.2 billion people (UNCCD, 2024)

UNCCD (UN Convention to Combat Desertification)

Feature Detail
Adopted 1994 (Paris); entered into force December 1996
Parties 197 parties (near-universal)
Objective Combat desertification and mitigate the effects of drought, particularly in Africa, through effective action supported by international cooperation and partnership arrangements
Implementation National Action Programmes (NAPs) developed by each party
India Ratified 1996
COP-14, New Delhi India hosted the 14th Conference of Parties in September 2019 (2--13 September, New Delhi); PM announced India would raise its land restoration target from 21 Mha to 26 million hectares by 2030
COP-16, Riyadh December 2024; focused on drought resilience and land tenure

Land Degradation Neutrality (LDN)

Feature Detail
Concept A state where the amount and quality of land resources necessary to support ecosystem functions and services remain stable or increase within specified temporal and spatial scales and ecosystems (UNCCD definition)
SDG linkage SDG Target 15.3: "By 2030, combat desertification, restore degraded land and soil, including land affected by desertification, drought and floods, and strive to achieve a land degradation-neutral world"
India's LDN target Restore 26 million hectares of degraded land by 2030 (announced at UNCCD COP-14, 2019)
Approach Avoid -- Reduce -- Reverse: avoid new degradation, reduce existing degradation, reverse/rehabilitate already degraded land
Indicators Monitored through 3 sub-indicators: (1) land cover change; (2) land productivity dynamics; (3) soil organic carbon stocks

For Prelims: UNCCD: adopted 1994; 197 parties; India ratified 1996; India hosted COP-14 (New Delhi, September 2019); India's LDN target = restore 26 Mha by 2030. SDG Target 15.3 = land degradation neutrality.

Soil Health Initiatives in India

Soil Health Card (SHC) Scheme

Feature Detail
Launched 19 February 2015 by PM Modi in Suratgarh, Rajasthan
Objective Provide every farmer with a Soil Health Card containing crop-wise recommendations for nutrients and fertilisers based on soil testing
Coverage (February 2025) Over 24.74 crore Soil Health Cards generated; 25 crore+ distributed to farmers
Soil testing labs 8,272 Soil Testing Laboratories across India; 665 Village-level Soil Testing Labs in 17 states
Financial support Rs 1,706 crore provided to states/UTs since inception
Soil mapping Completed at 1:10,000 scale across nearly 290 lakh hectares; 1,987 village-level soil fertility maps in 21 states
Impact Helps farmers optimise fertiliser use -- reduce excess application, address deficiencies, improve soil health and crop yields
Challenges Card distribution =/= farmer adoption; many farmers do not alter fertiliser practices based on SHC recommendations; testing quality varies; need for repeat testing

Organic Farming — Paramparagat Krishi Vikas Yojana (PKVY)

Feature Detail
Launched 2015--16 as a sub-scheme under Rashtriya Krishi Vikas Yojana (RKVY)
Objective Promote organic farming through a cluster-based approach -- end-to-end support from production to processing, certification, and marketing
Coverage (January 2025) ~15 lakh hectares under organic farming; 52,289 clusters formed; 25.30 lakh farmers benefited
Financial assistance Up to Rs 50,000/hectare for 3 years; 60% for input costs (organic manure, seeds, bio-pesticides); 40% for value addition, marketing, and certification
Budget released Rs 2,266 crore released since 2015
India's global position 4th in the world in terms of certified organic farming area (IFOAM Statistics 2022)
Certification Through PGS (Participatory Guarantee System) -- a cost-effective, community-based certification model

Zero Budget Natural Farming (ZBNF)

Feature Detail
Concept Farming method that eliminates external input costs -- no chemical fertilisers, pesticides, or purchased seeds; uses locally available biological resources
Key inputs Jeevamrit (fermented microorganism culture), Beejamrit (seed treatment), mulching, mixed cropping
Promoter Subhash Palekar (Padma Shri); Andhra Pradesh adopted as state policy (Community-Managed Natural Farming -- CMNF)
Scale Andhra Pradesh targets 6 million farmers across 8 million hectares; over 10 lakh farmers practising as of 2025
Debate Proponents claim significant yield maintenance with zero input cost; critics question scalability and yield potential for staple crops

For Mains: India's soil health strategy encompasses testing (SHC), organic farming (PKVY), and natural farming (ZBNF). However, the fundamental challenge remains: the Green Revolution model of high external input agriculture (chemical fertilisers, pesticides, intensive irrigation) has degraded soils over decades. Transitioning to sustainable agriculture requires not just schemes but a systemic shift in input subsidies, procurement policy, and farmer education.

Agroforestry and Soil Conservation

Sub-Mission on Agroforestry (SMAF)

Feature Detail
Launched 2016--17 under the National Mission for Sustainable Agriculture (NMSA)
Objective Encourage farmers to plant trees on farmland alongside crops; integrates agriculture with forestry for ecological and economic benefits
Benefits for soil Tree roots bind soil, reduce erosion; leaf litter adds organic matter; trees provide windbreaks; nitrogen-fixing trees (e.g., Leucaena, Gliricidia) enrich soil
Financial support Rs 1 lakh/hectare assistance for planting; state nurseries; demonstration plots
National Agroforestry Policy, 2014 India was the first country to adopt a dedicated national agroforestry policy

Conservation Agriculture

Principle Detail
Minimum soil disturbance Zero-till or minimum tillage -- reduces soil compaction, preserves soil structure, protects earthworms and microbial communities
Permanent soil cover Mulching with crop residues or cover crops; prevents erosion, retains moisture, regulates soil temperature
Crop diversification Rotation of cereals with legumes, oilseeds, and vegetables; breaks pest/disease cycles; legumes fix atmospheric nitrogen, enriching soil
India's adoption Happy Seeder technology for zero-till wheat sowing in rice-wheat systems (Punjab, Haryana) -- also addresses stubble burning
Impact Studies show conservation agriculture improves soil organic carbon by 0.2-0.5% over 5-10 years; reduces input costs; maintains or improves yields after initial transition period

Soil Erosion in River Basins

River Basin Key Soil Erosion Challenge
Ganga basin Bank erosion in middle and lower reaches; sedimentation of reservoirs; erosion from Shivalik hills; erosion-induced flooding in Bihar
Brahmaputra basin Among the highest sediment loads globally; massive bank erosion in Assam (Majuli island shrinking); flash floods carry sediment from Himalayan slopes
Chambal ravines One of the most severe gully erosion landscapes in India; ravines extend across MP, Rajasthan, UP; Chambal ravine reclamation programmes underway
Western Ghats Sheet and landslide erosion on steep slopes; exacerbated by deforestation and plantation monocultures; laterite soil highly susceptible
Coastal erosion Coastal erosion affects ~45% of India's non-rocky coastline; Sundarbans (West Bengal), Chellanam (Kerala), parts of Odisha and Tamil Nadu most vulnerable

For Mains: Soil erosion is not just an agricultural problem -- it is a disaster management, river conservation, and climate change issue. Erosion deposits sediment in rivers and reservoirs, reducing storage capacity and increasing flood risk. Integrated watershed management that addresses erosion at source is more cost-effective than downstream flood management.

Land Use Change

Urbanisation and Soil Sealing

Feature Detail
Scale India's urban area has expanded from ~2.99% of total area (2001) to ~3.5% (2021); projected to increase significantly as 600 million people are expected to live in cities by 2030
Impact Permanent loss of fertile agricultural and forest land; soil sealing by concrete/asphalt eliminates soil functions (water infiltration, carbon storage, biodiversity habitat)
Hotspots Peri-urban agricultural land around metros (Delhi NCR, Bangalore, Hyderabad, Pune) under severe conversion pressure

Mining and Reclamation

Feature Detail
Impact Open-cast mining removes topsoil entirely; overburden dumps, tailings, and acid mine drainage contaminate surrounding land and water
Legal requirement Mine Closure Plan mandatory under Mineral Conservation and Development Rules; Progressive Mine Closure during operation + Final Mine Closure after cessation
CAMPA Compensatory Afforestation Fund used for rehabilitation of mining areas in forest land
Challenges Reclamation often inadequate; restored sites rarely achieve pre-mining ecological quality; abandoned mines (legacy sites) remain unreclaimed

Watershed Management

PMKSY — Watershed Development Component (WDC-PMKSY 2.0)

Feature Detail
Background Integrated Watershed Management Programme (IWMP) launched 2009--10; amalgamated into PMKSY in 2015--16
Current phase WDC-PMKSY 2.0 (2021--2026)
Physical target 49.50 lakh hectares
Central outlay Rs 8,134 crore (indicative)
Objective Restore ecological balance by conserving degraded natural resources -- soil, vegetative cover, and water; prevent soil erosion, regenerate vegetation, harvest rainwater, recharge groundwater
Approach Ridge-to-valley treatment; activities include contour bunding, terracing, check dams, percolation tanks, farm ponds, afforestation, and pasture development

Soil Carbon Sequestration

Feature Detail
What Process by which atmospheric CO2 is captured and stored in soil organic matter through photosynthesis and decomposition
Potential Soils globally store ~2,500 GtC (more than atmosphere + vegetation combined); increasing soil organic carbon by even a small percentage can sequester significant CO2
India's relevance Indian soils have low organic carbon content (~0.3--0.5% in most agricultural soils vs 1--3% in temperate soils); significant potential to increase through agroforestry, cover cropping, conservation agriculture, and organic farming
4 per 1000 Initiative Launched at COP21 (Paris, 2015); aims to increase soil organic carbon stocks by 0.4% per year globally; India is a participant

UPSC Relevance

Prelims Focus Areas

  • Soil degradation types: water erosion, wind erosion, salinisation, waterlogging, acidification, nutrient depletion
  • ISRO/SAC data: 96.4 Mha degraded (~29.3% of India); Rajasthan = most degraded state
  • UNCCD: adopted 1994; 197 parties; India ratified 1996; COP-14 in New Delhi (September 2019)
  • India's LDN target: restore 26 Mha by 2030; SDG Target 15.3
  • Soil Health Card: launched February 2015; 24.74 crore cards generated; 8,272 labs
  • PKVY: organic farming; 15 lakh hectares; 25.30 lakh farmers; Rs 50,000/hectare
  • ZBNF: Subhash Palekar; AP state policy; Jeevamrit, Beejamrit
  • WDC-PMKSY 2.0: 2021--2026; 49.50 lakh hectares; Rs 8,134 crore

Mains Focus Areas

  • Soil degradation as a threat to food security -- types, causes, and extent in India
  • UNCCD and Land Degradation Neutrality -- India's targets, progress, and challenges
  • Soil health management -- SHC scheme effectiveness, organic farming (PKVY), ZBNF debate
  • Land use change -- urbanisation of agricultural land, mining impacts, and reclamation
  • Watershed management -- integrated approach to soil and water conservation
  • Soil carbon sequestration -- potential for climate change mitigation through sustainable land management
  • Policy integration -- linking soil health with water conservation, food security, and climate action

Vocabulary

Desertification

  • Pronunciation: /dɪˌzɜːrtɪfɪˈkeɪʃən/
  • Definition: The degradation of land in arid, semi-arid, and dry sub-humid areas resulting from various factors including climatic variations and human activities such as deforestation, overgrazing, unsustainable agriculture, and urbanisation -- leading to the loss of biological productivity and the impoverishment of terrestrial ecosystems, distinct from natural desert expansion.
  • Origin: From English desert (from Latin desertum, "an abandoned place") + the suffix -ification ("the process of making"); the term gained prominence in the 1970s following the devastating Sahel drought (1968--1974) in West Africa, which led to the UN Conference on Desertification (Nairobi, 1977) and eventually the adoption of UNCCD in 1994.

Salinisation

  • Pronunciation: /ˌsælɪnaɪˈzeɪʃən/
  • Definition: The accumulation of water-soluble salts -- primarily sodium chloride (NaCl), sodium sulphate (Na2SO4), and calcium sulphate (CaSO4) -- in the soil profile to levels that adversely affect plant growth and soil structure, typically caused by irrigation without adequate drainage, capillary rise of saline groundwater in waterlogged areas, or intrusion of seawater in coastal zones.
  • Origin: From Latin salinus ("of salt", from sal, "salt") + -isation; soil salinisation has been a challenge since the earliest irrigated civilisations -- the decline of ancient Mesopotamian agriculture is partly attributed to salinisation caused by poor irrigation practices over millennia.

Key Terms

Soil Health Card (SHC) Scheme

  • Pronunciation: /sɔɪl hɛlθ kɑːrd skiːm/
  • Definition: A flagship Government of India scheme launched on 19 February 2015 under which every farmer receives a Soil Health Card once every two years, containing a printed report of the nutrient status of the soil (12 parameters: pH, EC, organic carbon, N, P, K, S, Zn, Fe, Cu, Mn, B) along with crop-wise recommendations for dosage of fertilisers and soil amendments required to maintain soil health and optimise productivity.
  • Context: As of February 2025, over 24.74 crore SHCs have been generated with 8,272 Soil Testing Laboratories operational across India and Rs 1,706 crore released to states; the scheme completed 10 years in 2025; while distribution coverage is impressive, the key challenge remains farmer adoption -- studies show many farmers do not alter their fertiliser use based on SHC recommendations.
  • UPSC Relevance: GS3 (Agriculture, Environment). Prelims: launched February 2015; 24.74 crore cards; 8,272 labs; 12 soil parameters tested. Mains: evaluate the SHC scheme's effectiveness in promoting balanced fertiliser use and improving soil health; discuss challenges in farmer behaviour change and soil testing infrastructure.

Land Degradation Neutrality (LDN)

  • Pronunciation: /lænd ˌdɛɡrəˈdeɪʃən njuːˈtræləti/
  • Definition: A state in which the amount and quality of land resources necessary to support ecosystem functions and services and enhance food security remain stable or increase within specified temporal and spatial scales -- achieved through the "Avoid-Reduce-Reverse" framework: avoiding new degradation, reducing ongoing degradation, and reversing past degradation through rehabilitation and restoration.
  • Context: LDN is central to SDG Target 15.3 ("achieve a land degradation-neutral world by 2030"); India committed to restoring 26 million hectares of degraded land by 2030 at UNCCD COP-14 (New Delhi, 2019); progress is monitored through three sub-indicators: land cover change, land productivity dynamics, and soil organic carbon stocks.
  • UPSC Relevance: GS3 (Environment). Prelims: SDG 15.3, India's target (26 Mha by 2030), UNCCD COP-14 (New Delhi, 2019). Mains: discuss India's progress towards LDN targets; analyse the adequacy of current policies (watershed management, afforestation, soil health programmes) in achieving land degradation neutrality.

Sources: ISRO/Space Applications Centre (Desertification and Land Degradation Atlas of India), UNCCD (Convention text, COP-14 outcomes, LDN framework), pib.gov.in (Soil Health Card scheme, PKVY, PMKSY, UNCCD COP-14), Ministry of Agriculture (SHC data, PKVY data), Department of Land Resources (WDC-PMKSY 2.0), IFOAM (organic farming statistics), 4 per 1000 Initiative