IAN Seminar Series

We used two approaches to study the interactive effects of land use and shoreline armoring on submerged aquatic vegetation (SAV) in Chesapeake Bay. One approach developed spatial-statistical models relating SAV abundance to land use and shoreline armoring. The models exploited bay-wide data on land cover, shoreline hardening, and decades of annual SAV mapping. The second approach was a field study of SAV abundance along transects extending offshore from natural and riprapped shorelines. Both approaches show that human land uses, especially cropland and developed land, and shoreline armoring can have negative impacts on SAV. However, the effects differ among salinity zones, probably because the dominant SAV species and associated stressor-response relationships also differ with salinity.• Local watershed land use affects subestuary SAV abundance, which is lower subestuaries with in watersheds dominated by agriculture or developed land.• Shoreline hardening can reduce SAV abundance. The effects differ among sal