Title of Dissertation: MACROINVERTEBRATE COMMUNITY STRUCTURE AND ECOLOGICAL FUNCTION IN MARYLAND COASTAL PLAIN STREAMS

Abiotic conditions within streams, especially those conditions impacted by human activities, often influence the community structure and ecosystem function. While coastal regions have been strongly impacted by urban development and agriculture, little research has focused on characterizing the biotic community structure and function in these Coastal Plain streams. Such watersheds are characterized by low gradient, blackwater streams with sandy and silty substrate, coupled with large amounts of human disturbance. The objectives of this research were 1) to characterize the macroinvertebrate community and the chemical and physical characteristics of two Coastal Plain watersheds with differing landuse practices, 2) to examine appropriate macroinvertebrate sampling protocol comparing leaf pack and Maryland Biological Stream Sampling (MBSS) methods, 3) to compare these community structure measures with the functional measure 1 of leaf decomposition, and 4) to investigate potential mechanisms for shifts in decomposition due to elevated nutrients and dissolved organic carbon (DOC) concentrations in mesocosms. Results of three years of monthly sampling showe