Mississippi State University
Date of Degree
Graduate Thesis - Open Access
Wildlife and Fisheries Science
Master of Science
College of Forest Resources
Department of Wildlife, Fisheries and Aquaculture
Installation of low-grade weirs in agricultural drainage ditches is being evaluated as an innovative, and cost effective, management practice that decreases nutrient concentrations and loads by increasing water volume and hydraulic residence time of the ditch. Results revealed that weirs significantly increased (P = 0.029) hydraulic residence time (HRT) and ditch water volumes, leading to considerable reductions in outflow water volumes (61%). Furthermore, ditches with weirs achieved greater (P = 0.09) cumulative outflow load reductions (96%) and greater (P = 0.029) concentration reductions during the biogeochemical reduction phase of the experiment. Similarly, field research from Terrace Ditch in Yazoo County, MS yielded significant percentage concentration reductions for baseflow (53%), stormflow (63%), and load (65%). Results from the experimental approach and field scale research offer promising insight into the future of low-grade weir’s establishment as an additional best management practice in agricultural landscapes.
Littlejohn, Alex, "Nutrient Mitigation Capacity of Low-Grade Weirs in Agricultural Drainage Ditches" (2012). Theses and Dissertations. 3336.