Shaping pollinator diversity through coffee agroforestry management: A meta‐analytical approach

Abstract

Abstract Pollinator diversity plays an important role in improving the resilience of pollination services. However, agricultural intensification is causing declines in pollinator diversity. Such losses could be mitigated and even reversed by agroforestry systems, whose structural complexity exceeds that of intensive agricultural systems. Research, primarily conducted in tropical regions, suggests that efficiently managing agroforestry systems can increase pollinator diversity. We performed a global meta‐analysis to explore how coffee agroforestry management practices affect the diversity of bee pollinators. We employed 137 sets of results from 20 studies that had been conducted at widely distributed locations across four of the seven continents. More specifically, we investigated the impact of augmenting floral resources (60 sets of results) and shade‐tree cover (43 sets of results) and reducing the distance to natural forests (34 sets of results). Additionally, we examined key moderating factors, including climatic conditions, pollinator sociality, the metrics used to describe pollinator diversity, pollinator sampling methods, the metrics used to characterise the effects of management practices and floral resource type. We observed that bee pollinator diversity broadly increased as local floral resources increased in tropical coffee agroforestry systems. Shade‐tree cover and proximity to natural forests did not broadly influence bee pollinator diversity. However, the strength and direction of the relationships between the agroforestry management practices and bee pollinator diversity were moderated by different factors, mainly climatic conditions and pollinator sociality. Our findings underscore the importance of managing coffee agroforestry systems to maximise bee diversity, which is crucial for coffee plant pollination. The broader objective should be to ensure the availability of resources that promote pollinator fitness, effective pollination and, as a consequence, crop yields.