Kaycee Reynolds, graduate student, will defend her master's degree thesis at 10 a.m., April 17 in Hardin Hall, Room 901.
Reynolds' thesis is titled, "Water quality in agricultural watersheds: Exploring patterns, fluxes and uncertainties using high-frequency data." Her adviser is Amy Burgin.
Abstract:
The inherently dynamic nature of climate-landscape interactions in agricultural watersheds makes evaluation of nitrate (NO3-) fluxes from these ecosystems complex. Understanding NO3- loading to agricultural streams requires optimization of monitoring strategies. A spatially distributed, high-frequency water quality monitoring network has expanded to cover ~40% of Iowa, providing direct observations of in situ NO3- concentrations at a 15-minute resolution. In this study, NO3- records were systematically subsampled allowing quantification of uncertainty in annual mean NO3- concentration and total flux estimates for conventional sampling strategies. In addition, seasonal trends in nitrate concentration response for more than 400 storms were explored using high-resolution data. As climate becomes more erratic, high-resolution NO3- monitoring will conceivably offer an improvement in our understanding of coupled hydrological and biogeochemical system interactions.