Forest edges buffer effects of agricultural management on bee–plant interaction networks

Abstract

Bee–plant interaction networks are essential for sustaining pollination services in agricultural landscapes, and farming practices can modify their structure by altering species composition and interaction patterns along crop margins. This study assessed how conventional and organic management influence bee–plant interaction networks and key network metrics (connectance, nestedness, interaction richness, interaction diversity and modularity) along crop field edges bordering native forest fragments. Surveys conducted on farms growing different crops revealed similar bee and plant species richness between management systems. However, conventionally managed farms were characterized by a greater dominance of supergeneralist species, such as Apis mellifera Linnaeus, 1758, and Trigona spinipes (Fabricius, 1793), resulting in higher network connectance. In contrast, organically managed farms exhibited greater interaction richness and interaction diversity but lower connectance, indicating a broader distribution of interactions among species rather than a greater number of interacting taxa. The presence of flowering plants along crop borders in both systems promoted active bee–plant networks regardless of management type. Our results highlight the importance of crop edges and adjacent native vegetation in maintaining pollination processes across agricultural systems. They also suggest that a shared landscape context and similar floral resources can reduce expected differences between organic and conventional management, thereby mitigating potential negative effects of conventional practices on pollination networks.