Landscape structure and land use affect estuarine benthic invertebrates in the Virginian Biogeographic Province, USA.

Estuaries are dynamic transition zones linking freshwater and oceanic habitats. These productive ecosystems are threatened by a variety of stressors including human modification of coastal watersheds. In this study, we examined potential linkages between estuarine condition and the watershed using multimodel inference. We examined attributes at the watershed scale as well as those associated with riparian areas but found that they were highly correlated. We also examined whether attributes closer to the estuary were more strongly related to benthic invertebrate condition and found that this was not generally true. In contrast, variability within the estuary strongly impacted model results and suggests that future modeling should incorporate estuarine variability or focus on the individual stations within the estuary. Modeling estuarine condition indicated that inherent landscape structure (e.g., estuarine area, watershed area, watershed:estuary ratio) is important to predicting benthic invertebrate condition and needs to be considered in the context of watershed/ estuary planning and restoration.