Data from: Influence of agricultural intensification on pollinator pesticide exposure, food acquisition and diversity

Pollinators are essential for maintaining sustainable crop production,
while the decline of pollinators is a widespread concern. Agricultural
intensification is one of the primary drivers of the decline of insect
pollinators. Agricultural intensification usually involves a decreasing of
non-crop semi-natural habitat and an increasing of pesticide exposure for
pollinators. However, causal links between agricultural intensification,
increased pesticide exposure, and reduced pollinator’s food sources and
pollinator diversity remain underexplored. We assessed pollinator
diversity across a landscape gradient where the proportion of rice ranged
from 11% to 85% in South China. We placed honeybee (Apis mellifera) and
mason bee (Osmia excavata) in these landscapes and investigated pesticide
exposure in honeybee  foragers and pollen, and in mason bee
pollen and nesting materials. We also assessed  the acquisition
of food by mason bees. We found a higher frequency of pesticide detection
in honeybee foragers and honeybee pollen samples in areas with a higher
proportion of rice fields. There was a strong positive relationship
between mason bee food acquisition and the proportion of semi-natural
habitats, while no significant effects of pesticide exposure on pollinator
diversity were found in addition to the effect of semi-natural habitat.
Synthesis and applications: Our results suggest that pollinator
communities could be at an increased risk of pesticide exposure due to
intensified agriculture, while the negative impact on pollinator diversity
mainly results from the loss of habitat and/or reduced food sources. This
study highlights the importance of conserving semi-natural habitat to
mitigate the causes of decline in pollinator diversity. We also recommend
long-term, multi-year studies to further understand the mechanisms behind
the loss of pollinators in farming landscapes.