Organic farming drives higher diversity of beetles, with more predators and less pests

Abstract

Agricultural intensification has led to significant species losses and has been associated with a decline in ecosystem services proved by insects. Reconciling biodiversity and agriculture production is a key challenge of the 21st century, for which solutions such as organic farming emerge, but remain to be tested in a wide range of ecological and socio-economic contexts. In Asia, particularly in Lao PDR, biodiversity-friendly agricultural practices such as the production of organic crops have been promoted to address these challenges, although intensification continues to progress. In this study, we examined beetle community composition in three organic and three conventional farming systems in Vientiane, Lao PDR. Our results indicate that beetle abundance was relatively consistent in both farm types, while species richness was higher in organic farming compared to conventional farming. Furthermore, predators were over 18 times more abundant, and insect pests 9 times less abundant, in organic farming, suggesting an enhanced pest control. Abundance and richness of beetles also exhibited seasonal variation during the year. These findings have enormous significance for the promotion of sustainable agriculture and the preservation of biodiversity in Southeast Asia and tropical countries in general, and they greatly advance our understanding of the ecological effects of various farming methods. They may also contribute to assisting government policy, particularly the Ministry of Agriculture, which plays a crucial role in promoting and supporting the development of organic agriculture in Lao PDR.