Insect–flower interactions: network structure in organic versus conventional vineyards

Abstract

AbstractEcosystems are made up of various mutualistic and antagonistic plant and animal interactions. These interactions are subject to various global change phenomena such as land use change and habitat modification. While the effect of environmentally friendly farming practices on the taxonomic diversity of plants and animal species has been reported, it is uncertain whether these schemes provide benefit for species interaction networks. We compared insect–flower interaction networks by analyzing important web structure indices from organic and conventional vineyards and natural vegetation sites in five different localities in the Cape Floristic Region biodiversity hotspot. Average number of insect–flower interactions was higher in organic vineyards compared with conventional vineyards and natural sites. Abundance of flowering plants contributed significantly to explain the observed difference in number of interactions in the model. Other network indices were similar between the different land use types. Our results support the importance of less intensive farming for promoting biodiversity. Approaches such as organic farming are especially beneficial for important interaction networks that drive the process of maintaining biodiversity. The potential of well‐managed vineyard ecosystems for promoting conservation of ecologically important insect–flower interactions is demonstrated.