Estimating the Nutrient and Sediment Pollution Impacts of Land Use Conversion in the Chesapeake Bay

Abstract

The Chesapeake Bay faces ongoing challenges regarding excess nutrient and sediment pollution as a result of increased urbanization which threatens aquatic ecosystem health. To address these challenges, the Chesapeake Legal Alliance is interested in exploring the relationship between land use conversion and resulting nutrient and sediment pollution loads delivered to the Bay. Our retrospective geospatial analysis from 2013 to 2018 on land use conversion in Anne Arundel county, Maryland reveals that estimated natural land use acreage decreased by 0.75%, developed land use acreage increased by 4.33%, and agricultural land use acreage decreased by 1.43%. These changes to land use within our study area, along with the Chesapeake Assessment Loading Tool (CAST) projections, estimate that total phosphorus loadings decreased by 3.02%, nitrogen loadings decreased by 1.97%, and sediment loadings decreased by 1.38%. Our findings are presented as an interactive dashboard at the parcel-level across Anne Arundel county, with a focus on parcels that experienced significant land use change.