Crop diversification enhances yields, biodiversity, and ecosystem services

The article “Positive but variable effects of crop diversification on biodiversity and ecosystem services”, published in Global Change Biology on 18 July 2021, assembles for the first time a substantial body of empirical evidence on the positive impacts of cultivated biodiversity on agroecosystems. The first author Damien Beillouin, a CIRAD agronomic data analysis specialist, stresses the scope: “Most studies to date have been scattered. Here we synthesised the quantified impacts of over 5,000 field studies from across the globe, from 1936 to now.”

The article is a large-scale synthesis review conducted by a Franco-Dutch research team, including a compilation of the results of 95 meta-analyses, 5,156 studies and 54,554 experiments spanning 85 years and representing more than 120 crop species in 85 countries. Crop diversification was found to enhance crop production by 14% and associated biodiversity by almost 25%. Water quality was improved by 50%, pest and disease control by over 63% and soil quality by 11%. The authors—scientists from CIRAD, INRAE and VU University Amsterdam—distinguished between the diversification strategies implemented, while highlighting the excellent performance of agroforestry-based systems.