Conservation Agriculture (CA)
Concept & Definition
- Conservation agriculture is a resource-efficient, sustainable crop production system aimed at achieving high productivity while conserving soil, water, and biodiversity.
- FAO defines CA as “a concept for resource-saving agricultural crop production that strives to achieve acceptable profits together with high and sustained production levels while concurrently conserving the environment.”
In short: “Produce more with less” while protecting the natural resource base.
Basic Principles of CA
- Minimal Soil Disturbance; No-tillage or reduced tillage. Avoid ploughing, to preserve soil structure, reduce erosion, and save energy.
- Permanent Soil Cover; Maintain residue mulch (crop residues, cover crops). Prevents erosion, conserves moisture, improves soil organic matter.
- Diverse Crop Rotations/Associations; Rotations with legumes, cover crops, and intercropping. Enhances biodiversity, breaks pest/disease cycles, improves nutrient use efficiency.
Key Practices in Conservation Agriculture
- Zero Tillage (ZT): Direct seeding without prior soil disturbance.
- Residue Retention: 30–50% of crop residues kept on soil surface.
- Crop Diversification: Use of legumes, cover crops, intercropping.
- Integrated Nutrient Management (INM): Balanced use of organic & inorganic fertilizers.
- Integrated Pest Management (IPM).
- Efficient Water Management: Laser land leveling, micro-irrigation, rainwater harvesting.
- Precision Farming Tools: Herbicide application, site-specific nutrient management.
Benefits of Conservation Agriculture
(A) Soil Health
- Improves soil organic carbon and microbial activity.
- Reduces erosion and soil compaction.
- Enhances soil structure and porosity.
(B) Water Conservation
- Improves infiltration and water-holding capacity.
- Reduces evaporation losses (residue cover).
- Enhances water use efficiency (WUE).
(C) Crop Productivity & Sustainability
- Stabilizes yields across years.
- Improves Sustainability Yield Index (SYI).
- Reduces input costs (fuel, labor, irrigation).
(D) Environmental Benefits
- Reduces GHG emissions (less CH₄ & CO₂ from tillage).
- Carbon sequestration in soils.
- Reduces air pollution (avoids stubble burning).
(E) Economic & Social Benefits
- Lower cost of cultivation.
- Higher B:C ratio.
- Saves time (faster sowing of wheat after rice).
Constraints in Adoption of CA
- Farmers’ reluctance due to traditional mindset.
- Lack of appropriate machinery (zero-till drills, residue managers).
- Weed infestation (due to no tillage, reliance on herbicides).
- Initial cost of CA machinery is high.
- Lack of awareness, training, and policy support.
Examples in India
- Rice–Wheat System (Indo-Gangetic Plains): Zero tillage wheat after rice → reduces turnaround time, improves yield stability, saves water and fuel. Residue retention helps prevent stubble burning in Punjab & Haryana.
- Maize–Wheat/Maize–Legume Systems: Improved soil fertility, better water productivity.
- CA in rainfed regions: Use of cover crops and mulching to conserve moisture.
Conservation Agriculture vs. Conventional Agriculture
Aspect |
Conventional Agriculture |
Conservation Agriculture |
Tillage |
Intensive ploughing |
Zero/Minimum tillage |
Residues |
Removed/burned |
Retained as mulch |
Cropping |
Monoculture |
Diversified (rotation, intercropping) |
Soil Health |
Declines over time |
Improves soil structure & fertility |
Input use |
High fuel, labor, inputs |
Reduced inputs, efficient use |
Environment |
More GHG emissions |
Reduced emissions, carbon sequestration |