Fostering pollination through agroforestry: A global review

Abstract

Over time, agricultural systems have undergone intensification with a view to increasing food production and security. However, the resulting land use conversions have led to declines in biodiversity and ecosystem services, such as pollination, and have thus negatively affected food production and security. It may be that the harmful impacts of conventional agriculture could be somewhat mitigated by diversifying current farming systems. Notably, the incorporation of agroforestry can provide suitable habitat for native pollinators and thus maintain pollination services. In recent years, several studies have examined pollination dynamics in agroforestry systems. However, their findings remain scattered, and the effects of agroforestry practices on pollination have generally been approached from a theoretical rather than an experimental point of view. Here, we reviewed the literature published to date on pollination in agroforestry systems across the world with a view to identifying general trends, gaps in knowledge, and future opportunities. To this end, we systematically characterized and quantified the research based on its biogeographical, economic, and ecological facets, and we synthesized discoveries about how agroforestry practices influence pollinators and pollination services. Our results highlight that, compared to conventional agriculture, agroforestry generally promotes or maintains pollination services. Therefore, this review supports the perspective that agroforestry systems represent a sustainable alternative to conventional agricultural systems. Future research should focus on improving understanding of how crop management intensity, irrigation, and organic inputs affect pollination services. We need more studies looking at a broader range of crop species and pollinator guilds as well as research examining the effects of crop management intensity on plant-pollinator interaction networks.