Influence of Agrochemical Mixtures on Treatment Wetland Ecosystems Services

Wetlands are used across the United States for treating agricultural runoff. Agricultural runoff can contain a number of constituents including nutrients, antibiotics and nitrification inhibitors. This project will evaluate the discrete and combined effects of specific veterinary and human antibiotics and an increasingly-used nitrification inhibitor (nitrapyrin) on nitrate-N treatment efficiency in saturated sediments and floating treatment wetlands. Our project objectives are: (1) simulate and quantify the degradation kinetics for antibiotics, nitrapyrin and nitrate-N in a floating treatment wetland; (2) determine the impact of agrichemical mixtures on denitrification and microbial community structure in wetland soils; and (3) evaluate the influence of site history on the removal of nitrate-N in wetlands. The interdisciplinary team assembled for this project provides a rare opportunity to evaluate an important ecosystem service of wetlands (i.e. water treatment) from an integrated microbiology, biogeochemistry, analytical chemistry, and environmental and agricultural engineering perspective. The proposed project will enhance agricultural sustainability by improving water quality of runoff entering surface and groundwater in agroecosystems. Further, the project will focus on the biogeochemical processes affecting fate and transport of three critical agrochemicals prevalent in agroecosystems within a novel on-site treatment system. Further, the project will evaluate design parameters that will enhance the treatment potential of floating treatment wetland systems. These systems provide several ecosystem services to agroecosystems including water treatment, habitat, biodiversity, carbon storage, and aesthetics. Wetland removal rates for CECs and nutrients will be quantified and can be used to improve process-based models to analyze CEC and nutrient lifecycles in agroecosystems.