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Analysis Of Surface Water For Irrigation In The Big Sunflower River Watershed, Meredith Lynn Brock
Analysis Of Surface Water For Irrigation In The Big Sunflower River Watershed, Meredith Lynn Brock
Theses and Dissertations
Exploitation of groundwater and excess nutrient runoff are major issues plaguing agriculture and streams in the Lower Mississippi River Basin, and increased irrigation intensity has yielded a proportionate increase in water use. Quantifying the use and effects of conservation practices like on-farm water storage (OFWS) systems will justify continued adoption of these practices to mitigate groundwater decline and nutrient runoff. Since 2010, over 795 hectares of surface water storage has been added in the Big Sunflower River Watershed, and analysis of aquifer saturation shows a recent rise in the water table and a decrease in seasonal water table drawdowns. Modeling …
Geospatial Analyses Of Groundwater Depletion And Contamination: Multiscale - Global, Regional And Local Analyses, Aynaz Lotfata
Geospatial Analyses Of Groundwater Depletion And Contamination: Multiscale - Global, Regional And Local Analyses, Aynaz Lotfata
Theses and Dissertations
The overarching objective of this dissertation was to study groundwater resources on global, local, and regional scales. The first objective of this dissertation was to analyze the groundwater nitrate contamination in the Edwards-Trinity and the Southern High-Plains aquifers of Texas. The second was to study groundwater quality in terms of seawater intrusion in the California Coastal Basin, Upper Floridian, and North Atlantic Coastal Plain aquifers. This dissertation also provided a comprehensive overview of the groundwater level in basins at the global scale and further analyzed agricultural activities on groundwater storage in small and large basins. To achieve first objective, Ordinary …
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. …
Methodology To Predict Daily Groundwater Levels By The Implementation Of Machine Learning And Crop Models, Sandra Milena Guzman Gutierrez
Methodology To Predict Daily Groundwater Levels By The Implementation Of Machine Learning And Crop Models, Sandra Milena Guzman Gutierrez
Theses and Dissertations
The continuous decline of groundwater levels caused by variations in climatic conditions and crop water demands is an increased concern for the agricultural community. It is necessary to understand the factors that control these changes in groundwater levels so that we can better address declines and develop improved conservation practices that will lead to a more sustainable use of water. In this study, two machine learning techniques namely support vector regression (SVR) and the nonlinear autoregressive with exogenous inputs (NARX) neural network were implemented to predict daily groundwater levels in a well located in the Mississippi Delta Region (MDR). Results …
An Examination Of The Hydrological Environment In Choctaw County Mississippi Since 1995, With A Focus On An Area Surrounding An Industrial Complex Established In 1998, Jeremy Keith Foote
An Examination Of The Hydrological Environment In Choctaw County Mississippi Since 1995, With A Focus On An Area Surrounding An Industrial Complex Established In 1998, Jeremy Keith Foote
Theses and Dissertations
The population and industrial complexes of Choctaw County obtains much of its water from an aquifer system in the Tertiary age Wilcox unit of the Mississippi Embayment. Utilizing 20 years of physical chemistry (P-Chem) analysis, potentiometric groundwater records of Choctaw County public water wells as well as industrial P-Chem analysis and surface and ground water level records from an industrial complex, this study examined the changes to the hydrosphere that has taken place since 1995. Analysis of the hydrosphere shows that over the last 20 years, there has been a drop in the potentiometric surface of the Wilcox aquifer system. …
Surface-Water And Groundwater Interactions Of A Stream Reach And Proposed Reservoir Within The Pascagoula River Basin: George County, Mississippi, Courtney Killian
Surface-Water And Groundwater Interactions Of A Stream Reach And Proposed Reservoir Within The Pascagoula River Basin: George County, Mississippi, Courtney Killian
Theses and Dissertations
This research had two main objectives: quantify surface-water and groundwater interactions along a stream reach, and determine the hydraulic conductivity at the site where two reservoirs are proposed. The objectives of this research aim to help maintain stream ecology and increase surface water storage for recreational and industrial purposes. The stream reach, located in the Pascagoula River Basin of southeast Mississippi, begins at Lake Okatibbee and terminates at Pascagoula into the Gulf of Mexico. Four USGS continuous gauging stations provided more than forty years of stream discharge data for a hydrograph baselow-recession analysis, which determined the baseflow component within the …
Development Of An Integrated Suite Of Methods To Reduce Computational Effort In Groundwater Modeling Validation And Testing, Jacqueline Pettway
Development Of An Integrated Suite Of Methods To Reduce Computational Effort In Groundwater Modeling Validation And Testing, Jacqueline Pettway
Theses and Dissertations
A suite of tools to reduce the computational effort in groundwater modeling validation and testing has been developed. The work herein explores reduction of computational effort via smart adaptivemeshing, optimization techniques, which require fewer model calls, and the development of surrogate models. Adaptive meshing reduces the computational domain by allowing for mesh refinement in areas of interest determined dynamically by the model through error indicators instead of requiring a priori knowledge or a posteriori determination and rebuilding of the computational domain. As the areas of interest change with the physics, the refinement is removed to lower computational time by using …
Development Of An Interactive Model Predicting Climatological And Cultural Influences On Annual Groundwater Volume In The Mississippi Delta Shallow Alluvial Aquifer, Tia Leni Merrell
Theses and Dissertations
Water volume in the shallow alluvial aquifer in the Mississippi Delta region is subject to seasonal declines and annual fluctuations caused by both climatological variability and crop water use variations from year-to-year. The most recently documented water volume decline in the aquifer is estimated at 500,000 acreeet. Available climate, crop acreage, irrigation water use, and groundwater decline data from Sunflower County, MS are used to evaluate the climate-groundwater interactions in the Mississippi Delta region. This research produced a model that simulates the effects of climatic variability, crop acreage changes, and specific irrigation methods on consequent variations in the water volume …
Hydrogeologic Conditions Controlling Contaminant Migration From Storage Tanks Overlying Mississippi River Alluvium, Jay N (Jay Nicholas) Santucci
Hydrogeologic Conditions Controlling Contaminant Migration From Storage Tanks Overlying Mississippi River Alluvium, Jay N (Jay Nicholas) Santucci
Theses and Dissertations
Delta Store #3033 in Indianola, MS is suspected of having had a release of petroleum, which may have contaminated the underlying soil and shallow groundwater. Exploratory boring/monitoring wells were drilled on-site noting all soil formations and groundwater encountered. The soil facies encountered show a fining upward sequence, representative of a fluvial depositional environment. Soil contamination is mostly confined to the surficial soil; however, evaluation of lab data, boring logs, and cross sections suggests it is likely the contamination migrated through the surficial confining layer into the underlying strata. The hydraulic conductivity of 1.2 x 10-5 cm/sec, surficial geology consisting mostly …
The Geology And Hydrology Of The Proposed Upper Mccurtain Creek Watershed Impoundment Choctaw County, Mississippi, Leonard D (Leonard Dwight) Rawlings
The Geology And Hydrology Of The Proposed Upper Mccurtain Creek Watershed Impoundment Choctaw County, Mississippi, Leonard D (Leonard Dwight) Rawlings
Theses and Dissertations
The McCurtain Creek watershed was proposed for a large reservoir project resulting in the commissioning of this study to assess the site?s geology, hydrogeology, and surface hydrology to find whether or not the site was suitable. Data was collected from 57 geophysical logs from coal exploration boreholes to produce geologic and aquifer cross sections. A program to assess discharge identified surface hydrology characteristics of the stream at five locations. Twenty-seven geotechnical boreholes, 23 standpipe piezometers, and the data from the coal exploration were used to map the water table using ArcGIS 8.3 software. Eighteen piezometers at stream sites, used to …