Diverse Cropping Systems That Promote Beneficial Insects.

Recent shifts in agricultural production have resulted in increased pesticide use, land use intensification, and landscape simplification, all of which threaten biodiversity in and near farms. Here, we show that weakening arthropod species networks on farms results in greater pest pressure. Decreasing species diversity, community evenness, and weakening linkage density and decentralized network topology within a community is associated with greater insect pest abundance on maize farms. The scale and context of this study (53 operating farms and complete bioinventories of foliar communities), novel application of network analysis, and strength of the conclusions represent major advances for food security and land management. They also provide further justification for diversifying farmland to improve its resiliency against stressors.