Biodiversity Conservation in Agroecosystems Enhances Food Security and Environmental Sustainability: Evidence from Multi-Site Field Experiments

Abstract

To analyse the effect of biodiversity conservation in agroecosystems on food security and environmental sustainability, we performed a multi-site field experiment at 20 agricultural research farms under different agroecological zones. The experiment was conducted in a randomised complete block design with 360 experimental plots with three replications in three successive cropping seasons. Crop residue retention, conservation tillage, crop diversification, cover cropping, establishment of hedgerows, Integrated Pest Management, pollinator habitat restoration and organic farming were the practices studied. When these practices were implemented, we found an increase in plant species richness by 33.5%, an increase in number of pollinators by 30.8% and an increase of crop yield by 24.8%. Further, food security outcomes gained 27.8%, ecosystem services 31.2% and carbon sequestration 26.5%, respectively. From multiple linear regression results, it can be seen that plant species richness (standardised β = 0.48, p < 0.001), the number of pollinators (standardised β = 0.42, p < 0.001) and soil microbial biomass (standardised β = 0.36, p < 0.001) significantly affect food security and sustainability (R² = 0.793). The results of the correlation analysis revealed a high positive correlation between the Biodiversity Conservation Index and the Food Security Index (r = 0.86, p < 0.001). Three major factors with a total variance of 85.0% were also obtained in principal component analysis, which were the dimensions of biodiversity conservation, soil health and food security. In all indicators, the biodiversity conservation practices showed greater values than conventional farming systems. These results highlight the empirical evidence of the potential of any in-field biodiversity-friendly practice in the specific field to benefit in terms of increased food production, better ecosystems' health and better climate resilience, contributing to the process of agricultural transition towards sustainable agriculture.