(441b) Geospatial Analysis of Dependence on Pollination Ecosystem Services, Wild Bee Abundance, and Toxic Pesticide Loads

All engineering activities are dependent directly or indirectly on the availability of ecosystem goods and services. Yet, they remain highly underappreciated in engineering design and analysis and often not quantified in most sustainability assessments. One such service is the insect-mediated pollination. Insect pollinators provide a critical ecosystem service to approximately 75 agricultural crops in the United States. However, the support given to this service via conservation, management, and policy efforts does not correspond to the magnitude of the service provided, which is infinite. Consequently, human controlled inputs to agricultural sectors such as land use and pesticide application rarely have pollinator conservation in mind. Remarkably, even though the volume of pesticides applied annually had declined, the toxic load on insect pollinators is rising due to the increasing potency of current insecticides. Pollinator conservation is needed now more than ever as nearly half of all wild insect species are rapidly declining, and the beekeeping industry experiences further honeybee colony losses and increased demand due to agricultural intensification. The lack of valuation of pollination services in agricultural sectors is due to the complex nature of plant pollinator systems including variations in climate, cultivar, and management techniques which make analysis challenging. Hence, the required scale of analysis for targeted conservation is lacking, with most analysis only enabling a county level resolution, which does not provide resolution at the field scale, where conservation techniques are most needed and impactful.

We previously quantified the economic dependence of United States crops on insect-mediated pollination services at the county level. Building on our previous work and utilizing available data on bee abundance and pesticide use data, we present fine-scale analysis (30 x 30-meter resolution) of temporal trends in economic dependence on pollinators, wild bee abundance, and pesticide use over a 15 year time period (1997-2012) in the United States. We utilize a previously developed spatial model which incorporates habitat, local forage, national land cover data, and expert opinion to quantify wild bee abundance in the United States [1]. Previous analysis has identified regions of high vulnerability where economic dependence on pollination services is high but predicted wild bee abundance is low. Coupling this analysis with spatially-explicit available pesticide use and toxic load data provides a key factor to assessing the vulnerability of pollination services spatially and also assess a potential means of causation. We utilize a previous study which quantified bee toxic load from 1997-2012 by integrating crop landcover data, pesticide application rates, and pesticide toxicity [2]. The enhanced spatial resolution in our work provides greater specificity and more field scale context to vulnerable areas, where economic dependence is high, predicted wild be abundance is low, and pesticide toxic load is high. This further provides a framework to enable targeted, future studies, land management strategies, integrated pollinator pest management plans, and conservation in these vulnerable fields.

References

1. Koh, I., et al., Modeling the status, trends, and impacts of wild bee abundance in the United States. 2016. 113(1): p. 140-145.
2. Douglas, M.R., et al., County-level analysis reveals a rapidly shifting landscape of insecticide hazard to honey bees (Apis mellifera) on US farmland. Scientific Reports, 2020. 10(1).