Crop diversity in the landscape boosts pollinators and yield of pollinator dependent crops across the world.

Abstract

There is a global concern about the decline of wild pollinators and the ecosystem services they provide. Although land-use change is a major threat to biodiversity, it is still poorly understood how land-use heterogeneity (or land-use structure) impacts pollinator communities and entomophilous crop production. Based on a literature review, we performed a meta-analysis to (1) assess how landscape structure, both composition and configuration, affects pollinator species richness and abundance, and (2) examine the impact of landscape structure on the production of key entomophilous crops. We extracted information on pollinator communities and crop production from 101 studies with a total of 920 site replicates distributed widely across the globe. To obtain landscape structure (total area of all crops, crop diversity, and landscape Shannon’s Diversity Index) information, we sourced data from the database Map-SPAM as well as satellite images. We found that pollinator species richness increased with the number of crop species in the surrounding area. Pollinator abundance increased with the number of different crops but decreased with increasing agricultural area in the surrounding landscape. Crop production of several crops was associated with landscape heterogeneity. Notably, fruit set increased with an increasing number of crop species in neighbouring fields and decreased with increasing agricultural area, that is, when nature is substituted with agriculture in the surrounding landscape. We also found positive correlations between edge density of an area and pollinator species richness and entomophilous crop production suggesting that edge density can be used as a landscape structure indicator to assess pollinator diversity. The effects of landscape structure were more pronounced in crops with high pollinator dependence, showing stronger relationships with both pollinator diversity and crop production. These findings highlight the importance of maintaining landscape heterogeneity through crop diversity and natural habitats to support pollinators and their services, though unmeasured factors such as intensification or local management may also play a role.