Eight years of conservation agriculture and crop diversification in the Indo-Gangetic Plains: Impacts on yields, nutrition, and multiple ecosystem services

Résumé fourni par la source

Conservation agriculture (CA) is promoted to raise productivity while improving resource use efficiency and environmental performance, yet multi-criteria evidence over longer timeframes remains limited. We report results from an eight-year field experiment in Karnal, India, comparing seven cereal-based cropping system scenarios that differed in crop rotation, tillage/bed systems, crop establishment, residue management, and legume integration. We evaluated grain productivity and stability, water and nutrient use efficiency, energy efficiency, global warming potential intensity (GWPi), soil properties and carbon stocks, grain nutritional composition, and economic returns using mixed models that accounted for repeated measurements within plots. CA-based diversified systems generally reduced irrigation requirements, improved irrigation water productivity, increased partial factor productivity of nutrients, and enhanced soil organic carbon and macronutrient contents, while lowering emission intensity relative to conventional rice–wheat systems. Scenario 5 (maize-wheat-mungbean on zero-till permanent beds with residue retention) showed strong performance across several domains, including productivity, nutrition, efficiency, GWPi, and net income, while Scenario 4 (maize-mustard-mungbean) achieved the highest net energy ratio and a large income gain. However, benefits were not uniform across all scenarios, and inclusion of a legume did not by itself ensure higher yield than the conventional rice–wheat–fallow system. These results highlight the need to strategically target diversification options based on crop sequence, management, and production context, as the benefits were not uniform across all scenarios.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.