Context:
In the backdrop of rising concerns over excessive nitrogen fertilizer use, environmental pollution, and climate stress on agriculture, a recent international scientific study highlights the potential of multispecies grasslands to sustainably support livestock feed production, especially in temperate and warming regions.
Key Highlights:
Study Details / Scientific Findings:
- Conducted across 26 temperate sites by an international research team.
- Compared multispecies grasslands (grasses + legumes + herbs) with monoculture grasslands.
- Multispecies mixtures produced equal or higher yields than monocultures.
- Achieved high productivity with moderate nitrogen fertilizer application.
- Optimal species composition:
- 30–70% legumes in the mixture.
Scientific Principle / Ecological Functioning:
- Legumes fix atmospheric nitrogen, enriching soil fertility.
- Nitrogen fixed by legumes benefits neighbouring grasses and herbs.
- Reduces dependence on synthetic nitrogen fertilizers.
Significance / Applications:
- Supports sustainable livestock farming.
- Reduces fertilizer costs and environmental externalities.
- Particularly effective in warmer temperate regions, aligning with climate change adaptation needs.
Relevant Prelims Points:
- Issue & Causes:
- Overuse of nitrogen fertilizers leads to soil degradation, water pollution (eutrophication), and greenhouse gas emissions (N₂O).
- Climate change stresses conventional monoculture systems.
- Key Concepts:
- Nitrogen Fixation: Biological conversion of atmospheric nitrogen into plant-usable forms by microbes.
- Monoculture: Cultivation of a single crop species over a large area.
- Legumes (Fabaceae): Plants hosting nitrogen-fixing bacteria (Rhizobium).
- Benefits:
- Higher or stable yields with lower fertilizer input.
- Enhanced soil health and biodiversity.
- Lower input costs for farmers.
- Challenges:
- Need for site-specific mixture design.
- Limited awareness and adoption among farmers.
Relevant Mains Points:
- Facts & Static Linkages:
- Aligns with concepts of agroecology and sustainable intensification.
- Supports India’s goals of reducing chemical fertilizer dependence.
- Conceptual Clarity:
- Biodiversity enhances ecosystem productivity and resilience.
- Legume-based systems create natural nutrient cycling.
- Way Forward:
- Promote multispecies grasslands through extension services.
- Integrate findings with climate-resilient agriculture policies.
- Encourage incentives for low-input, eco-friendly livestock systems.
- Adapt models to Indian agro-climatic zones.
UPSC Relevance (GS-wise):
- GS 3 (Environment & Ecology): Sustainable agriculture, nutrient pollution, biodiversity.
- GS 3 (Economy): Livestock productivity, input cost reduction, farm sustainability.
- Prelims: Nitrogen fixation, legumes, monoculture vs mixed cropping.