RELATIONSHIPS BETWEEN PHYSICAL AND CHEMICAL WATER QUALITY ACROSS LAND USES OF SOUTHERN OHIO
Degradation of geophysical and chemical water quality due to land use change is a growing concern. We assessed these impacts by surveying thirty-eight stream reaches across three study catchments with contrasting land use in southern and central Ohio. Sampling occurred seasonally in 2016-2017 for nutrient concentrations, in-stream habitat quality, and geomorphic parameters. Nutrient concentrations were found to vary seasonally and by catchment: total phosphorus and orthophosphate were highest in the mixed-use watershed and total nitrogen and nitrate were lowest in the forested watershed. As expected, stream habitat quality was higher in forested and mixed-use watersheds than in the agricultural watershed. Accounting for catchment land use, habitat quality increased with increasing median grain size and width:depth ratio. Total phosphorus and orthophosphate decreased with increasing median grain size, while orthophosphate concentrations were positively associated with glide habitat. Siltation, width-depth ratio, amount of instream cover, and relative proportion of pool/riffle/run habitat were not related to nutrient concentrations. Our results suggest that some fluvial geomorphic features may aid in regulating nutrient dynamics in streams, and highlight the potential role of stream restoration in improving stream habitat quality and reducing stream phosphorus loading.
Kay C. Stefanik (Primary Presenter/Author), The Ohio State University, firstname.lastname@example.org;
S. Mažeika P. Sullivan (Co-Presenter/Co-Author), The Ohio State University, email@example.com;
Lauren M. Pintor (Co-Presenter/Co-Author), The Ohio State University, firstname.lastname@example.org;
Kaiguang Zhao (Co-Presenter/Co-Author), The Ohio State University, email@example.com;