Pollinator Dependency and Regional Climate Affect Crop Yield Development Under Climate Change

Climate change is severely impacting insects and flowering plants in different ways. While effects on plants, pollinators and their interactions have been amply discussed, subsequent impacts on pollination are rarely assessed. Understanding climate-change effects on pollination is particularly important for insect-pollinated crops as it ultimately influences yield and hence food production. This study investigated crop-yield changes over 35 years in two climatically distinct regions in Germany (cool-moist vs. warm-dry). Yield differences among crops showing different levels of pollinator dependency (none, moderate, strong) were analysed in correlation with time (indirect climate-change measure) and a composite climate parameter (direct measure). Despite rising temperatures and droughts, yields in both regions increased over time across pollinator-dependency classes, likely due to increased productivity through technological advances. Marked differences in yield optima based on pollinator dependency and region were found in complementary, time-independent climate correlations. Long-term average values exceeded optimal yield conditions for moderately pollinator-dependent plants. Surprisingly, crops that strongly depend on pollinators showed increased yields with warmer, drier conditions, possibly due to fewer late frost events and climate-driven pollinator community shifts. Synthesis and applications. While further research addressing current limitations is needed, the results suggest future crop yields may become less stable despite technological advances, as climatic optima are exceeded for several crops. Additionally, the response of pollinator-dependent crops to progressing climate change strongly varies depending on the degree of dependence, emphasising the importance of considering these factors in yield predictions and climate adaptation strategies.