Linking ground-based monitoring programs and models to identify management responses to US dust emissions

Abstract:

Wind erosion and mineral dust emissions threaten agroecosystem productivity and sustainability, food security, and human health across global drylands. In the United States, aerosol monitoring programs have revealed that mineral dust particulate matter (PM) emissions are changing and potentially increasing risks to human health, transportation networks, and agriculture across the dry western states. However, while a reasonably good understanding of broad scale spatial patterns and temporal trends of atmospheric PM concentrations has been established, we still have a limited understanding of which landscapes are eroding, by how much, and when, and how land use and management are influencing landscape scale erodibility. The ability to connect PM emissions with land use and management drivers, in the context of regional land cover change and climate change, is critical for land managers to make informed selections of conservation practices. This presentation will describe an effort coordinated by the USDA Agricultural Research Service (ARS), as part of the Long-Term Agroecosystem Research (LTAR) network, and Natural Resources Conservation Service (NRCS) to develop new tools to inform management of wind erosion and PM emissions. Our approach leverages intensive, local-scale measurements collected by the National Wind Erosion Research Network (14 sites) to parameterize a physically-based dust emission model (AERO) that can be applied to large-scale standardized ecosystem monitoring datasets (>60,000 plots) collected by the Bureau of Land Management (BLM) Assessment, Inventory and Monitoring (AIM) strategy and NRCS National Resources Inventory (NRI). We describe application of AERO to the monitoring datasets and the use of ecological site concepts, captured in the online Ecosystem Dynamics Interpretive Tool (EDIT), to relate aeolian sediment transport rates and PM emissions to structural and functional attributes of rangeland ecosystems that control thresholds for erosion and dust emission. We show how incorporation of AERO estimates into EDIT will enable managers to directly link wind erosion and PM emission risks to ecosystem state changes and land management, and identify appropriate conservation practices.