Grassland: Problems and Management
- Importance of Grasslands
- Cover ~15–18% of India’s geographical area (but quality varies).
- Provide 70–80% of fodder for livestock.
- Conserve soil and water, prevent erosion.
- Serve as habitat for biodiversity.
- Low-cost feed resource for small farmers and pastoralists.
- Problems of Grasslands
Grasslands in India are highly degraded due to human and livestock pressure. Main problems:
Biotic Pressure
- Overgrazing: >2–3 times carrying capacity; reduces palatable grasses, increases weeds.
- Uncontrolled grazing: Continuous grazing prevents grass regeneration.
- Excess livestock population: India has ~535 million livestock (2020), but poor fodder base.
Soil and Environmental Problems
- Soil erosion: Overgrazing + deforestation → loss of topsoil.
- Low soil fertility: Deficiency of N, P, and micronutrients.
- Water scarcity: Most grasslands are rainfed; droughts reduce productivity.
- Salinity/alkalinity: In arid/semi-arid regions.
Botanical Composition
- Replacement of nutritious grasses (e.g., Cenchrus ciliaris) by unpalatable weeds (e.g., Parthenium, Lantana).
- Encroachment by shrubs and invasive species.
Socio-economic Issues
- Grazing is often unregulated/open access, leading to “tragedy of commons.”
- Lack of awareness among farmers about improved pasture management.
Management of Grasslands
Grassland management = scientific practices to improve productivity, quality, and sustainability.
Protection and Controlled Grazing
- Deferred grazing: Resting the pasture during early growth stages.
- Rotational grazing: Divide pasture into paddocks; graze in rotation.
- Controlled stocking: Maintain stocking rate = carrying capacity (~2–4 ha per cattle in semi-arid India).
- Zero grazing / Stall feeding: Cut-and-carry system in highly degraded areas.
Improvement of Existing Grasslands
- Reseeding/Overseeding: Introduce improved perennial grasses (Cenchrus ciliaris, Stylosanthes hamata).
- Weed control: Mechanical/chemical removal of weeds like Parthenium.
- Fertilizer application: Apply 40–60 kg N + 20–30 kg P₂O₅/ha/year.
- Moisture conservation: Contour bunding, trenches, water harvesting structures.
- Soil improvement: Gypsum for alkali soils, drainage for waterlogged areas.
Silvi-Pastoral System
- Integration of trees + grasses + legumes.
- Provides fodder + fuelwood + timber.
- Example: Leucaena leucocephala (Subabul) with Cenchrus ciliaris.
Introduction of Legumes
- Improve forage quality (protein content).
- Fix atmospheric N → improve soil fertility.
- Common legumes: Stylosanthes hamata, Clitoria ternatea, Lablab purpureus.
Controlled Burning; Used selectively to remove weeds and improve grass tillering (in some ecosystems).
- Community-based Management
- Village grazing lands (Gochar, Oran) → managed by panchayats.
- Participatory pasture development programs (under watershed development projects).
Examples of Grassland Regions in India
- Semi-arid grasslands: Rajasthan, Gujarat (dominated by Cenchrus ciliaris).
- Tropical humid grasslands: Bengal, Assam (Imperata cylindrica).
- Himalayan grasslands (Alpine pastures): Himachal, J&K (Festuca, Agrostis).
Key Facts for Exams
- Average productivity of Indian grasslands = 1–2 t/ha/yr DM (can be improved to 8–10 t/ha/yr with management).
- Carrying capacity of Indian grasslands = 0.2–0.5 adult cattle units (ACU) per ha (vs. 2–3 ACU/ha potential).
- India faces a 35–40% deficit of green fodder.
- Cenchrus ciliaris (Buffel grass) = most important grass for semi-arid pastures.
- Stylosanthes hamata = “wonder legume” for grassland improvement.
- Overgrazing; India has 20% of the world’s livestock but only 2% of the world’s grazing land. Overgrazing reduces plant cover, leading to soil erosion, compaction, and invasion of unpalatable weeds.
- Fodder Deficit: Deficit as per IGFRI, Jhansi: Green fodder → 35% deficit, Dry fodder → 10% deficit, Concentrates → 35% deficit
