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Investigating The Role Of Plant Traits And Interactions In Emergent Wetland Nutrient Removal, Andrew Ryan Sample
Investigating The Role Of Plant Traits And Interactions In Emergent Wetland Nutrient Removal, Andrew Ryan Sample
Theses and Dissertations
Increasing wetland restoration in the Lower Mississippi Alluvial Valley has been identified as a method to reduce nutrient loading in the Gulf of Mexico. Wetlands have historically been used to treat water through processes facilitated by wetland plants, and relatively few species and plant traits have been identified as important in carrying out these processes. This study focuses on some of those species and traits and aims to identify species differences and plant traits that may be important for wetland nutrient mitigation. Chapter I provides background information on nutrient pollution, wetland biogeochemical mechanisms for nutrient sequestration, and the focal species …
An Evaluation On The Effects Of Additions And Deletions Of Specific Nutrient Management Strategies On Corn Yield At Different Plant Densities, James D. Dew
Theses and Dissertations
Improved management strategies are needed to increase yield production and quality. The study aimed to determine suitable cultural practices for improved corn production. Experiments were set up at Verona and Stoneville, Mississippi, from 2020 to 2022. Treatments included row configurations (single and twin-row), plant populations (79,000 and 99,000 seeds ha-1), and six combinations of nutrients with or without fungicide. The nutrients evaluated were two nitrogen rates 235 and 314 kg N ha-1, phosphorus 45 kg P ha-1, potassium 112 kg K ha-1, sulfur 22 kg S ha-1, and zinc 11 kg Zn ha-1, and fungicide at 272 ml ha-1. In …
Utilization Of A Boosted Regression Tree Framework For Prediction Of Dissolved Phosphorus Concentrations Throughout The High Plains Aquifer Region, Jeffrey M. Temple
Utilization Of A Boosted Regression Tree Framework For Prediction Of Dissolved Phosphorus Concentrations Throughout The High Plains Aquifer Region, Jeffrey M. Temple
Theses and Dissertations
Groundwater-derived phosphorus has often been dismissed as a significant contributor towards surface water eutrophication, however, this dismissal is unwarranted, making the quantification of phosphorus concentrations in groundwater systems immensely important. Machine learning models have been employed to quantify the concentrations of various contaminants in groundwater, but to our best knowledge have never been used for the quantification of groundwater phosphorus. The goal of this research was to use a boosted regression tree framework to produce the first believed machine learning model of phosphorus variability in groundwater, with the High Plains aquifer serving as the study area. Results display a boosted …
Phosphorus Occurrence And Origin In The Mississippi River Valley Alluvial Aquifer In Northwestern Mississippi, Claire Elise Rose
Phosphorus Occurrence And Origin In The Mississippi River Valley Alluvial Aquifer In Northwestern Mississippi, Claire Elise Rose
Theses and Dissertations
The median total dissolved phosphorus concentration (0.41 mg/L P) of groundwater from the Mississippi River Valley alluvial aquifer exceeded the U.S. Environmental Protection Agency’s stream nutrient criteria (of 0.1 mg/L P) and the national background for phosphorus in groundwater (0.02 mg/L P). A general association between elevated phosphorus and dissolved iron concentrations suggests that reducing conditions that mobilize iron in the aquifer also may facilitate transport of phosphorus. These elevated concentrations of phosphorus may indicate phosphorus in the study area may be concentrated through irrigation return flow and groundwater discharge, and may contribute to the Gulf of Mexico hypoxic zone. …
Evaluation Of Sediment And Nutrient Loss During The Revegetation Of Mississippi Roadsides, Kyle R. Briscoe
Evaluation Of Sediment And Nutrient Loss During The Revegetation Of Mississippi Roadsides, Kyle R. Briscoe
Theses and Dissertations
Runoff during the revegetation of roadsides can transport sediment and nutrients offsite, leading to surface water quality reductions. Two field experiments were conducted near Starkville, MS in 2011 and 2012 to evaluate the influence of N and P sources and rates, fertilization timing, and mulch type on vegetative establishment and nutrient and sediment runoff losses. Stainless steel runoff frames (0.75 x 2.0 m) were installed on 10% and 15% slopes for Experiment I and Experiment II, respectively. A bahiagrass (Paspalum notatum Flugge), tall fescue [Schedonorus arundinaceus (Schreb.) Dumort., nom. cons.], sericea lespedeza [Lespedeza cuneata (Dum. Cours.) G. Don], and common …
Pond Management Approaches And Effects On Trophic Dynamics, Michael Scott Sherman
Pond Management Approaches And Effects On Trophic Dynamics, Michael Scott Sherman
Theses and Dissertations
Mississippi has an abundance of ponds which provides a number of opportunities for anglers. Several enhancement strategies are used to improve fish production in ponds, including fertilizing and supplemental feeding. These strategies may ignore the potential ecological impacts that may unexpectedly arise, such as prolific plant growth. This study consists of two phases; first, a mesocosm experiment investigating fertilizer application rates (mg P/L) in relation to potential sunfish growth, and second, a replicated pond experiment consisting of four treatments to simulate commonly used enhancement strategies. Mesocosm experiment showed a peak of sunfish growth at the 0.6 mg P/L level and …
Sediment And Phosphorus Dynamics Behind Weirs In Agricultural Drainage Ditches, Elizabeth Louise Usborne
Sediment And Phosphorus Dynamics Behind Weirs In Agricultural Drainage Ditches, Elizabeth Louise Usborne
Theses and Dissertations
Low grade rip rap weirs installed in agricultural surface drainage ditches manage downstream eutrophication by slowing water flow, allowing sediments time to settle out of the water column and phosphorus (P) to sorb to soil. A laboratory experiment was conducted in microcosm chambers to simulate increased hydraulic residence time caused by weirs and two field studies were conducted to compare experimental data with field data and determine sediment deposition rates. One field study monitored weirs monthly after installation and the other measured weirs of varying ages. Weirs retained significantly more water and sediment than controls. Longer inundation times led to …
Development Of A Nutrient And Dissolved Oxygen Water Quality Model For The Saint Louis Bay Watershed, Janna Marie Kieffer
Development Of A Nutrient And Dissolved Oxygen Water Quality Model For The Saint Louis Bay Watershed, Janna Marie Kieffer
Theses and Dissertations
Nutrient enrichment, which can be detrimental to the health of aquatic systems, is one of the leading causes of impairment of our Nations? waters. Development and initial calibration of a hydrologic, hydrodynamic, and water quality model of dissolved oxygen and nutrient concentration for the St. Louis Bay watershed in coastal Mississippi is documented herein. The model was developed using the USEPA BASINS 3.0 analysis system and WinHSPF, a comprehensive watershed loading and transport modeling software. The resulting model simulates significant watershed and instream physical, chemical and biological processes including rainfall runoff and associated water quality from a variety of land …