Global agricultural productivity is threatened by increasing pollinator dependence without a parallel increase in crop diversification.

The global increase in the proportion of land cultivated with pollinator-dependent crops implies increased reliance on pollination services. Yet agricultural practices themselves can profoundly affect pollinator supply and pollination. Extensive monocultures are associated with a limited pollinator supply and reduced pollination, whereas agricultural diversification can enhance both. Therefore, areas where agricultural diversity has increased, or at least been maintained, may better sustain high and more stable productivity of pollinator-dependent crops. Given that >80% of all crops depend, to varying extents, on insect pollination, a global increase in agricultural pollinator dependence over recent decades might have led to a concomitant increase in agricultural diversification. We evaluated whether an increase in the area of pollinator-dependent crops has indeed been associated with an increase in agricultural diversity, measured here as crop diversity, at the global, regional, and country scales for the period 1961-2016. Globally, results show a relatively weak and decelerating rise in agricultural diversity over time that was largely decoupled from the strong and continually increasing trend in agricultural dependency on pollinators. At regional and country levels, there was no consistent relationship between temporal changes in pollinator dependence and crop diversification. Instead, our results show heterogeneous responses in which increasing pollinator dependence for some countries and regions has been associated with either an increase or a decrease in agricultural diversity. Particularly worrisome is a rapid expansion of pollinator-dependent oilseed crops in several countries of the Americas and Asia that has resulted in a decrease in agricultural diversity. In these regions, reliance on pollinators is increasing, yet agricultural practices that undermine pollination services are expanding. Our analysis has thereby identified world regions of particular concern where environmentally damaging practices associated with large-scale, industrial agriculture threaten key ecosystem services that underlie productivity, in addition to other benefits provided by biodiversity.

Aizen MA ，Aguiar S ，Biesmeijer JC ，Garibaldi LA ，Inouye DW ，Jung C ，Martins DJ ，Medel R ，Morales CL ，Ngo H ，Pauw A ，Paxton RJ ，Sáez A ，Seymour CL ... -  《-》

How much does agriculture depend on pollinators? Lessons from long-term trends in crop production.

Aizen MA ，Garibaldi LA ，Cunningham SA ，Klein AM ... -  《-》

Wild insect diversity increases inter-annual stability in global crop pollinator communities.

Senapathi D ，Fründ J ，Albrecht M ，Garratt MPD ，Kleijn D ，Pickles BJ ，Potts SG ，An J ，Andersson GKS ，Bänsch S ，Basu P ，Benjamin F ，Bezerra ADM ，Bhattacharya R ，Biesmeijer JC ，Blaauw B ，Blitzer EJ ，Brittain CA ，Carvalheiro LG ，Cariveau DP ，Chakraborty P ，Chatterjee A ，Chatterjee S ，Cusser S ，Danforth BN ，Degani E ，Freitas BM ，Garibaldi LA ，Geslin B ，de Groot GA ，Harrison T ，Howlett B ，Isaacs R ，Jha S ，Klatt BK ，Krewenka K ，Leigh S ，Lindström SAM ，Mandelik Y ，McKerchar M ，Park M ，Pisanty G ，Rader R ，Reemer M ，Rundlöf M ，Smith B ，Smith HG ，Silva PN ，Steffan-Dewenter I ，Tscharntke T ，Webber S ，Westbury DB ，Westphal C ，Wickens JB ，Wickens VJ ，Winfree R ，Zhang H ，Klein AM ... -  《-》

Long-term global trends in crop yield and production reveal no current pollination shortage but increasing pollinator dependency.

Aizen MA ，Garibaldi LA ，Cunningham SA ，Klein AM ... -  《CURRENT BIOLOGY》

Temporal Trends in Pollination Deficits and Its Potential Impacts on Chinese Agriculture.

Worldwide, there is increasing evidence that shows a decline in pollinators, limiting crop pollination and production. However, it is unclear to what extent Chinese agriculture could be impacted by pollinator deficits. Data for 84 major crops in China between 1961 and 2018 were analyzed for the temporal trends in crop area and production, agricultural economic contribution of pollination, crop yield deficits, and honey bee pollination demand. We found a rapid increase in agricultural dependence on insect pollinators: both the cultivated area and total production of pollinator-dependent crops increased faster than those of pollinator-independent crops during 1961-2018. The total economic value of pollination amounted to US$ 106.08 billion in 2010, representing 19.12% of the total production value of Chinese agriculture, approximately twice the 9.5% value estimated for global agriculture. Crops with higher pollinator dependence showed greater mean growth in cultivated area than those with lower dependence, but lower mean growth of crop production and yield. Crop yield growth was also more unstable with increasing pollinator dependence. The minimum pollination demand for honey bee colonies was about three times the stock of honey bee colonies available in 2018. Furthermore, we found a decline in crop yield deficit with the increase in honey bee colony pollination service capacity. We considered that the shortage of pollinators resulted in the yield deficits for pollinator-dependent crops. Future increase in the area of pollinator-dependent crops will increase the need for more pollinators, suggesting the importance of implementing measures to protect pollinators to ensure a better-secured future for agricultural production in China.

Mashilingi SK ，Zhang H ，Chen W ，Vaissière BE ，Garibaldi LA ，An J ... -  《-》