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Thursday, January 25, 2018. 12:00PM. Webinar: Human influence at the coast: Upland and shoreline stressors affect coastal benthic macrofauna. Rochelle D. Seitz, Virginia Institute of Marine Science. Sponsored by Center for Satellite Research and Applications. More information here.

Anthropogenic stressors can affect subtidal communities within the land-water interface. Increasing anthropogenic activities, including upland and shoreline development, threaten ecologically important species in these habitats. In this study, we examined the consequences of anthropogenic stressors on benthic macrofaunal communities in 14

subestuaries of Chesapeake Bay. We investigated how subestuary upland use (forested,

agricultural, developed land) and shoreline development (riprap and bulkhead compared

to marsh and beach) affected density, biomass, and diversity of benthic infauna. Statistics

suggested that upland use and shoreline development were influenced benthic

communties. For benthic macrofauna, density tended to be lower in subestuaries with

developed or mixed compared to forested or agricultural upland use. Benthic biomass

was significantly lower in subestuaries with developed compared to forested upland use,

and biomass declined exponentially with proportion of near-shore developed land.

Benthic density did not differ significantly among natural marsh, beach, and riprap

habitats, but tended to be lower adjacent to bulkhead shorelines. In low salinities, benthic

diversity tended to be higher adjacent to natural marshes compared to the other habitats,

and lower adjacent to bulkheads, but the pattern was reversed in high salinities. Sediment

characteristics varied by shoreline type and contributed to differences in benthic

community structure. Living shorelines were effective in supporting nearshore benthic

communities in upper and lower Chesapeake Bay. Given the changes in the infaunal

community with anthropogenic stressors, subestuary upland and shoreline development

should be minimized to increase benthic production and subsequent trophic transfer

within the food web.