Evaluating the Impact of Hydrologic Variability and Land Use on Stream Ecosystem Health in the Piedmont Region
Authors
Deandre Presswood1* (dpresswood2@student.gsu.edu), Sarah H. Ledford1, Marie J. Kurz2
Institutions
1Georgia State University, Atlanta, GA; 2Oak Ridge National Laboratory, Oak Ridge, TN
Abstract
Land use and land cover change have strong impacts on aquatic metabolism in streams and rivers through changes in hydrologic regimes, light, nutrients, and other factors. However, efforts to quantify these relationships are difficult because of the disparate and convolved impact multiple changes can have on metabolism. This study utilizes a comprehensive dataset of stream metabolism modeled from dissolved oxygen from 2008 to 2021 across 11 sites in the Piedmont region of the U.S. southeast to investigate the response of aquatic ecosystems to fluctuations in hydrology, using resistance and resilience as key indicators. Resistance is defined as the degree to which production and respiration rates are altered by flow events, while resilience measures the time required for these rates to revert to their baseline levels following such events. The analysis further incorporates watershed land-use characteristics and a riparian vegetation index to categorize each site providing insights into the interplay between watershed characteristics and stream ecosystem health. This study is expected to reveal the dynamic responses of stream metabolism to fluctuating hydrologic conditions with a particular focus on how varying watershed characteristics and the presence of riparian vegetation might influence these interactions.