Geography
Soils and Natural Vegetation
Soil Erosion and Conservation
Soil erosion, degradation and conservation in India for CGPSC: sheet, rill, gully and wind erosion, ISRO land degradation atlas, Soil Health Card, watersheds.
Prerequisites
- Soil Types of India: which soils are thin, light or easily washed away
- Climate of India: intense monsoon bursts are the main driver of water erosion
- Physiographic Divisions of Chhattisgarh: the pats and plateaus where erosion is worst in the state
The Hook: The Red Water of the Mahanadi
Connect
Stand on a bridge over the Mahanadi or the Hasdeo in the first week of a heavy July rain. The water is red-brown. That colour is topsoil: soil that took centuries to form on the fields and slopes upstream, now on its way to the Bay of Bengal and into the reservoirs that were built to irrigate the same fields.
How does soil get lost, how much of India’s land is degrading, and what actually stops it?
Why it matters: Prelims asks the types of erosion, conservation methods, problem-soil remedies, institutions and scheme facts (Soil Health Card). Mains GS-III asks land degradation, desertification and watershed development, where a Chhattisgarh example earns marks.
Soil Erosion and Soil Degradation
| Term | Meaning |
|---|---|
| Soil erosion (मृदा अपरदन) | Removal of the topsoil by water or wind faster than new soil forms |
| Soil degradation / land degradation (भूमि निम्नीकरण) | Any decline in the soil’s productive capacity: erosion, but also salinity, waterlogging, loss of nutrients and organic matter, compaction, pollution |
| Desertification (मरुस्थलीकरण) | Land degradation in arid, semi-arid and dry sub-humid areas (the UNCCD definition) caused by climatic variation and human activity. It does not mean the spread of an existing desert only |
Erosion is natural at a slow geological rate. The problem is accelerated erosion caused by human activity.
Types of Erosion
By water (the most important agent in India)
flowchart LR
A["Splash
raindrops detach particles"] --> B["Sheet erosion
thin uniform layer
removed; hard to notice"]
B --> C["Rill erosion
small finger-like
channels on slopes"]
C --> D["Gully erosion
deep channels that
ploughs cannot cross"]
D --> E["Ravines / badlands
network of gullies
(Chambal valley)"]| Type | Feature | Indian example |
|---|---|---|
| Sheet erosion | A uniform thin layer of topsoil is washed off over a large area; the most fertile part goes first, and it often goes unnoticed | Gentle slopes of the peninsular plateau |
| Rill erosion | Water concentrates into small channels a few centimetres deep | Ploughed slopes after heavy rain |
| Gully erosion | Rills deepen into gullies; the land becomes unfit for ploughing | Plateau margins, mined areas |
| Ravines (बीहड़) and badlands | A dense network of deep gullies | Chambal valley (Madhya Pradesh, Rajasthan, Uttar Pradesh); also the Yamuna and Mahi valleys |
| Chos | Seasonal torrents eroding the foothills | Shiwalik foothills of Punjab (Hoshiarpur area) |
| Stream-bank and landslide erosion | Rivers cutting their banks; slope failure | Himalayan slopes, Brahmaputra banks |
By wind
- Wind lifts and carries loose, dry, fine soil, mainly in arid and semi-arid areas with little vegetation.
- Worst in western Rajasthan and adjoining Gujarat, Haryana and Punjab, especially in the hot, windy pre-monsoon months.
- Moving sand also buries fertile land, roads and canals.
Causes of Accelerated Erosion
| Cause | How it works |
|---|---|
| Deforestation | Removes the canopy and roots that break the impact of rain and bind the soil |
| Overgrazing | Strips grass cover; hooves loosen soil; common on village commons and forest fringes |
| Shifting cultivation | Slash-and-burn on slopes exposes soil; shorter fallow cycles make it worse. Called jhum in the north-east. In Chhattisgarh it survives in pockets, for example the penda of Abujhmarh and the bewar of the Baiga |
| Faulty farming | Ploughing up and down the slope, leaving land bare after harvest, removing bunds |
| Mining and construction | Open-cast mines and their dumps leave unprotected spoil; roads cut slopes |
| Over-irrigation | Not erosion as such, but causes waterlogging and salinity, the other big form of land degradation (Punjab, Haryana, canal command areas) |
| Climate | Short, intense monsoon bursts on bare soil; strong dry winds in the desert |
How Much Land Is Degrading?
The Desertification and Land Degradation Atlas of India, prepared by ISRO’s Space Applications Centre (SAC), Ahmedabad and released in June 2021, mapped the country for 2018–19:
| Indicator (2018–19) | Figure |
|---|---|
| Area under land degradation | 97.85 million hectares, about 29.7% of India’s total geographical area (328.72 Mha) |
| Area under desertification (drylands) | 83.69 million hectares (up from 81.48 Mha in 2003–05) |
| Largest single process | Water erosion, followed by vegetation degradation and wind erosion |
Date the number
Always write “about 30% of India’s land was degraded in 2018–19 (ISRO SAC Atlas, 2021)”. A newer atlas will replace these figures; quote whichever edition is latest when you write.
Soil Conservation Methods (मृदा संरक्षण)
On slopes and farmland
| Method | How it works | Where it fits |
|---|---|---|
| Contour ploughing (समोच्च जुताई) | Ploughing along the contour lines, not up and down; each furrow holds water | Gentle slopes, plateau fields |
| Contour bunding | Low earth bunds along contours slow runoff and trap soil | Peninsular uplands, Chhattisgarh’s Matasi and Bhata slopes |
| Terrace farming (सीढ़ीदार खेती) | Steps cut into the slope, each with a flat bench | Himalaya, north-east, Western Ghats |
| Strip cropping | Alternate strips of erosion-prone crops and cover crops (grass, legumes) | Slopes and windy plains |
| Mulching | Covering bare soil with crop residue or straw | Dry areas; also conserves moisture |
| Crop rotation and cover crops | Keeps land covered; legumes restore nitrogen | Everywhere |
| Gully plugging and check dams | Small barriers across gullies and streams reduce the speed of water and trap silt | Ravines, plateau streams |
| Afforestation and controlled grazing | Restores cover and roots; rotational grazing protects grass | Commons, degraded forest, catchments |
In dry and windy areas
- Shelter belts (रक्षक मेखला): rows of trees planted across the wind direction to cut wind speed.
- Sand dune stabilisation: grasses and shrubs planted on dunes, as researched by CAZRI, Jodhpur.
- Agroforestry with hardy trees such as khejri.
For problem soils
| Problem | Remedy |
|---|---|
| Alkaline / sodic (usar) | Gypsum, drainage, salt-tolerant crops |
| Saline and waterlogged | Sub-surface drainage, lining canals, avoiding over-irrigation |
| Acidic (laterite, red soils of high-rain areas) | Liming |
| Low organic matter | Farmyard manure, compost, green manure, crop residue retention instead of burning |
Watershed management (जलग्रहण क्षेत्र प्रबंधन)
A watershed is the area draining into one stream or outlet. Watershed management treats the whole unit from ridge to valley: afforestation and trenches on the ridge, bunds on the slopes, check dams and ponds in the drainage lines. It joins soil conservation, water harvesting and livelihoods, so it is the standard Mains answer to erosion in rain-fed areas.
Institutions and Policy
Research institutions (ICAR)
| Institution | Location | Focus |
|---|---|---|
| National Bureau of Soil Survey and Land Use Planning (NBSS&LUP) | Nagpur | Soil survey, mapping and land-use planning |
| Indian Institute of Soil Science (IISS) | Bhopal | Soil fertility and soil health |
| Indian Institute of Soil and Water Conservation (IISWC) | Dehradun | Erosion control and watersheds |
| Central Arid Zone Research Institute (CAZRI) | Jodhpur | Desert and dryland management |
| Central Soil Salinity Research Institute (CSSRI) | Karnal | Saline and alkaline soils |
Schemes and commitments
| Item | Key facts |
|---|---|
| Soil Health Card Scheme (मृदा स्वास्थ्य कार्ड) | Launched 19 February 2015 at Suratgarh (Rajasthan). Each card reports 12 parameters: N, P, K, S (macro); Zn, Fe, Cu, Mn, B (micro); pH, electrical conductivity, organic carbon, with fertiliser advice. Since 2022–23 it runs as the “Soil Health and Fertility” component of the Rashtriya Krishi Vikas Yojana |
| Watershed Development Component of PMKSY | Watershed development for rain-fed land under the Pradhan Mantri Krishi Sinchayee Yojana (launched 2015) |
| National Mission for Sustainable Agriculture | One of the missions under the National Action Plan on Climate Change; soil health and rain-fed area development |
| UNCCD (UN Convention to Combat Desertification, 1994) | India hosted COP14 in September 2019 (Greater Noida) and committed to restore 26 million hectares of degraded land by 2030 |
| Aravalli Green Wall Project | Launched in 2023: a green belt along the Aravalli range across Gujarat, Rajasthan, Haryana and Delhi to check land degradation and the eastward spread of the desert |
| Days | World Soil Day: 5 December. Desertification and Drought Day: 17 June. The UN marked 2015 as the International Year of Soils |
Chhattisgarh Angle
- Where erosion is worst: the pat uplands of Surguja–Jashpur, the margins of the Maikal range and the Bastar plateau, where slopes are steep, soils thin (Bhata, laterite, red sandy) and monsoon bursts heavy.
- Mining: open-cast coal in the Korba and Raigarh fields and iron ore at Bailadila leave dumps and bare land; spoil-dump stabilisation and mine reclamation matter here.
- Rain-fed paddy: large parts of the plain depend on the monsoon; farm ponds (dabri), field bunds and stream-line treatment hold both water and soil. The state has promoted narva (नरवा, stream) treatment with check dams and gully plugs since 2019.
- Forests protect the soil: with about 41% of its area under forest cover (ISFR 2023), the state’s catchments are relatively protected; keeping them forested protects reservoirs such as Minimata (Hasdeo) Bango from silting. See Forests and Wildlife of Chhattisgarh.
Analysis: Why Conservation Fails and What Works (Mains material)
- Erosion is invisible until it is too late. Sheet erosion removes the most fertile layer without the farmer noticing, so private incentives to invest are weak.
- Commons are nobody’s responsibility. Grazing land and village forests degrade fastest; community rules (joint forest management, village grazing plans) work better than isolated structures.
- Engineering without people fails. Check dams silt up and bunds break when they are not maintained. Watershed programmes succeed where the Gram Sabha (ग्राम सभा) and user groups own them.
- Soil health is chemical and biological too. Imbalanced fertiliser, residue burning and falling organic carbon are degradation even without erosion; soil testing and organic inputs address them.
- Climate change raises the stakes. More intense rainfall events increase water erosion; drylands face more droughts. Land degradation neutrality (LDN) by 2030 links soil to India’s climate and food-security goals.
Memory Tricks
Water erosion ladder: 'Some Simple Rains Grow Ravines'
Splash → Sheet → Rill → Gully → Ravine. Each step is deeper and harder to repair.
Institutions by city: 'Nagpur maps, Bhopal feeds, Dehradun holds, Jodhpur dunes, Karnal salts'
NBSS&LUP Nagpur (soil maps) · IISS Bhopal (fertility) · IISWC Dehradun (soil and water conservation) · CAZRI Jodhpur (desert) · CSSRI Karnal (salinity).
Soil Health Card: '12 on the card, 2015 at Suratgarh'
4 macro (NPKS) + 5 micro (Zn, Fe, Cu, Mn, B) + 3 others (pH, EC, OC) = 12.
Don’t Confuse
| This | vs | That |
|---|---|---|
| Sheet erosion: uniform thin layer, unnoticed | vs | Gully erosion: deep visible channels |
| Desertification: degradation in drylands (UNCCD) | vs | “Spread of the Thar desert” only |
| Gypsum: alkaline/sodic soils | vs | Lime: acidic soils |
| Contour ploughing: along the slope’s contour | vs | Ploughing up and down the slope (causes erosion) |
| Shelter belts: wind erosion | vs | Terracing: water erosion on steep slopes |
| CAZRI Jodhpur: arid zone | vs | CSSRI Karnal: salinity |
| World Soil Day 5 December | vs | Desertification and Drought Day 17 June |
Common Mistakes
MCQ traps
- “Wind is the main agent of soil erosion in India.” Wrong. Water erosion is the largest process nationally; wind dominates only in the arid west.
- “Desertification means the desert is expanding.” It means land degradation in drylands, wherever they are, including parts of Maharashtra, Karnataka or Jharkhand.
- “Sheet erosion is the most visible type.” It is the least visible; gullies and ravines are the visible ones.
- “The Soil Health Card was launched in 2014 in Gujarat.” It was launched on 19 February 2015 at Suratgarh, Rajasthan.
- “India’s land degradation target is 50 Mha by 2030.” The commitment is to restore 26 million hectares by 2030.
- “Contour ploughing means ploughing up and down the slope.” The opposite: along the contour, across the slope.
Practice
All questions below are original practice questions written in CGPSC style. They are not previous-year questions.
Level 1: Foundation
- The removal of a thin, uniform layer of topsoil over a large area is called ______ erosion.
- Rows of trees planted to reduce wind speed are called ______.
- The Soil Health Card Scheme was launched in ______ at Suratgarh, Rajasthan.
Answers
- Sheet erosion.
- Shelter belts.
- 2015 (19 February).
Level 2: Prelims MCQs
Q1. Consider the following statements about land degradation in India as per the ISRO Desertification and Land Degradation Atlas (2021):
- About 30% of India’s total geographical area was undergoing land degradation in 2018–19.
- Wind erosion was the most significant process of land degradation in the country.
- The atlas was prepared by the Space Applications Centre, Ahmedabad.
Which of the statements given above is/are correct?
- (a) 1 and 2 only
- (b) 2 and 3 only
- (c) 1 and 3 only
- (d) 1, 2 and 3
Answer and explanation
(c) 1 and 3 only. The atlas, prepared by SAC Ahmedabad, put land degradation at 97.85 million hectares, about 29.7% of the geographical area, in 2018–19. Statement 2 is wrong: water erosion was the largest process, followed by vegetation degradation and wind erosion.
Q2. Match List I (Problem) with List II (Remedy):
| List I | List II |
|---|---|
| A. Gully erosion | 1. Shelter belts |
| B. Wind erosion on sandy plains | 2. Gypsum |
| C. Alkaline (usar) soil | 3. Check dams and gully plugs |
| D. Acidic soil | 4. Liming |
- (a) A-3, B-1, C-2, D-4
- (b) A-1, B-3, C-2, D-4
- (c) A-3, B-1, C-4, D-2
- (d) A-2, B-1, C-3, D-4
Answer and explanation
(a) A-3, B-1, C-2, D-4. Check dams and gully plugs slow water and trap silt in gullies. Shelter belts break wind speed. Gypsum replaces sodium in alkaline soils. Lime neutralises acidity.
Q3. The Chambal valley is best known for which form of soil erosion?
- (a) Sheet erosion
- (b) Ravine (gully) erosion
- (c) Wind erosion
- (d) Coastal erosion
Answer and explanation
(b) Ravine erosion. The Chambal valley in Madhya Pradesh, Rajasthan and Uttar Pradesh has a dense network of deep gullies, the classic Indian ravines or badlands. Such land cannot be ploughed without major reclamation.
Q4. Which of the following parameters is not among the 12 reported on a Soil Health Card?
- (a) Organic carbon
- (b) Electrical conductivity
- (c) Soil temperature
- (d) Boron
Answer and explanation
(c) Soil temperature. The card reports N, P, K and S; zinc, iron, copper, manganese and boron; and pH, electrical conductivity and organic carbon. Temperature is not one of them.
Q5. Which ICAR institute is correctly matched with its location?
- (a) Central Arid Zone Research Institute: Bikaner
- (b) Central Soil Salinity Research Institute: Karnal
- (c) Indian Institute of Soil Science: Nagpur
- (d) Indian Institute of Soil and Water Conservation: Jodhpur
Answer and explanation
(b). CSSRI is at Karnal (Haryana). CAZRI is at Jodhpur, IISS at Bhopal, IISWC at Dehradun, and NBSS&LUP at Nagpur.
Level 3: Mains Answer Writing
Q1. (60 words) What is watershed management? Why is it suited to rain-fed areas of Chhattisgarh?
Model answer outline
- Definition: integrated treatment of the whole area draining to one outlet, from ridge to valley: plantations and trenches on top, bunds on slopes, check dams and ponds below.
- Suitability: rain-fed paddy on thin Bhata and Matasi soils; heavy monsoon runoff; it holds soil and water together and adds a rabi crop.
- Conclusion: works best when the Gram Sabha and user groups own and maintain it.
Q2. (150–200 words) “Land degradation is a silent crisis for Indian agriculture.” Discuss its causes and suggest measures, with reference to Chhattisgarh.
Model answer outline
- Intro: ISRO’s atlas (2021) found about 29.7% of India’s land (97.85 Mha) degraded in 2018–19; water erosion is the largest process.
- Causes:
- Deforestation and overgrazing on slopes and commons.
- Faulty farming: up-down ploughing, bare fallows, residue burning.
- Over-irrigation leading to salinity and waterlogging (Punjab, Haryana).
- Mining and infrastructure.
- Intense monsoon bursts, worsened by climate change.
- Measures: watershed development (PMKSY); contour bunding and terracing; shelter belts; gypsum and lime for problem soils; Soil Health Cards and organic manure; community management of commons; the national target of restoring 26 Mha by 2030.
- Chhattisgarh angle: erosion on pats and the Bastar plateau; coal and iron mining dumps (Korba, Bailadila); stream treatment with check dams; forest cover of about 41% (ISFR 2023) protecting catchments.
- Conclusion: soil is a slow-forming resource; prevention is far cheaper than reclamation.
Quick Revision Table
| Fact | Detail |
|---|---|
| Erosion sequence | Splash → sheet → rill → gully → ravine |
| Ravines | Chambal valley (MP, Rajasthan, UP) |
| Chos | Seasonal torrents, Shiwalik foothills of Punjab |
| Land degradation (2018–19) | 97.85 Mha, about 29.7% of India (ISRO SAC Atlas, June 2021) |
| Largest process | Water erosion |
| Desertification | 83.69 Mha in 2018–19 (drylands only) |
| Soil Health Card | 19 Feb 2015, Suratgarh; 12 parameters; under RKVY since 2022–23 |
| UNCCD | 1994; COP14 India, Sept 2019; 26 Mha restoration target by 2030 |
| Remedies | Gypsum (alkaline), lime (acidic), shelter belts (wind), terraces (slopes) |
| Institutes | NBSS&LUP Nagpur, IISS Bhopal, IISWC Dehradun, CAZRI Jodhpur, CSSRI Karnal |
| Days | World Soil Day 5 Dec; Desertification and Drought Day 17 June |
Key Takeaways
Key Takeaways
- Water erosion (sheet, rill, gully, ravine) is India’s largest land-degradation process; wind erosion dominates only in the arid west.
- About 30% of India’s land was degrading in 2018–19 (ISRO SAC, 2021).
- Conservation works at three levels: field (contour bunding, terracing, mulching), watershed (ridge-to-valley treatment) and soil chemistry (gypsum, lime, organic matter).
- Policy anchors: Soil Health Card (2015, 12 parameters), PMKSY watersheds, the 26 Mha by 2030 restoration target.
- In Chhattisgarh, erosion concentrates on thin upland soils, plateaus and mining areas; forests and watershed treatment are the main defences.
What’s Next
- Forest Types of India: the vegetation that holds the soil
- Soil Types of India: revise which soils are most vulnerable
- Environment and Ecology: conventions, climate change and ecosystems
- Agricultural Science: fertilisers, manures and integrated nutrient management
- Soils and Natural Vegetation: Quick Revision
Advertisement