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- Desorption (2)
- E. coli (2)
- Lidar (2)
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- Arid regions; Climate variability; Groundwater salinity; Reno (1)
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- Autosampler trigger (1)
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Articles 1 - 30 of 46
Full-Text Articles in Engineering
Laboratory Measurements Of Bed Shear Stress In Open Channel Flow And Soil Erosion Rate In Cohesive Soils, Gunnar Schurmann Kern
Laboratory Measurements Of Bed Shear Stress In Open Channel Flow And Soil Erosion Rate In Cohesive Soils, Gunnar Schurmann Kern
Electronic Theses and Dissertations
The relationship between soil erosion rate and bed shear stress is an important problem in sediment transport and scour. However, reliable measurements of the soil erosion function are challenging, both in the field and in the laboratory. The objective of this study is to investigate an experimental setup for conducting bed shear stress and soil erosion rate measurements using an open channel flume with a rough bed. These experiments were performed in an A-8 Hydraulic Channel with a fixed gravel bed. The flow discharge was kept constant at 0.158 ft.3/s, and bed shear stress was varied by changing the channel …
A Hydrologic Climate Study For An Arid Region, Ali Alsubeai
A Hydrologic Climate Study For An Arid Region, Ali Alsubeai
Electronic Theses and Dissertations
Water is the most precious natural resource in arid regions due to the limitation of water resources, expanding population, and increasing volumes of industrial and domestic waste. The purpose of this research was to evaluate methods to estimate water quantity in an arid region. The research consisted of three separate studies. In the first study, hydrologic models used to estimate water quantity were evaluated for suitability of use in arid regions. Most hydrologic models that have been used in arid regions were originally developed for humid regions. Rainfall events in arid regions can be characterized as short-term, high intense rainstorms …
Evaluating And Predicting The Risk Of Algal Blooms In A Freshwater Lake Through A 4-Dimensional Approach: A Case Study On Lake Mitchell, Sumit Kumar Ghosh
Evaluating And Predicting The Risk Of Algal Blooms In A Freshwater Lake Through A 4-Dimensional Approach: A Case Study On Lake Mitchell, Sumit Kumar Ghosh
Electronic Theses and Dissertations
Excessive algal growth in freshwater lakes can negatively impact ecosystems, recreation, and human health. Though algae are a natural part of freshwater ecosystems, elevated nutrient loading from anthropogenic and natural sources can lead to algal blooms. Both algae and blue-green algae (BGA) are responsible for algal blooms; however, BGA (cyanobacteria) is more dangerous. The first objective of this research was to prepare a conceptual model to understand how various environmental variables affect algae. This conceptual model was used to choose the environmental variables that help increase or decrease algae in the water environment. The second objective was to develop empirical …
A Hydrologic Study Of Climate Variability In Arid Region, Abdullah Alzaydani
A Hydrologic Study Of Climate Variability In Arid Region, Abdullah Alzaydani
Electronic Theses and Dissertations
Climate variability is an important subject to study. It is the change of climate over a long time, which could have a positive or negative impact on humans, soil, and wildlife. Many environments, such as arid environment could be affected by climate variability. The research goal is studying and examining climate variability in arid environment. The research includes three different studies. The first study includes reviewing and understanding of climate variability over extended time through existing studies in arid environments. In addition, this study includes knowledge about climate negative or positive impact on the environment. This study will be reviewing …
A Speciation Modeling Study Of Heavy Metal Adsorption To Plastic In Municipal Wastewater Treatment Plant Units, Kaitlyn Hague
A Speciation Modeling Study Of Heavy Metal Adsorption To Plastic In Municipal Wastewater Treatment Plant Units, Kaitlyn Hague
Electronic Theses and Dissertations
Microplastics are an emerging concern due to their harmful effect to organisms and their ability to facilitate transport of contaminants including heavy metals. Microplastics can enter the environment through wastewater treatment plants, landfill leachate, and littering. Once in the environment microplastics can be distributed throughout rivers, the ocean, and lakes. In order to understand the adsorption of heavy metals to microplastics a geochemical modeling study was completed using Visual Minteq. Lab tests were completed to better understand what constituents are available in wastewater at four different locations: influent, clarifiers, digesters, and effluent. These constituents were then used to observe how …
A Study Of Geographic Information System-Based Watershed Processing For Hydrologic Analysis Of Ungauged Watersheds, Philip Adanbe Adalikwu
A Study Of Geographic Information System-Based Watershed Processing For Hydrologic Analysis Of Ungauged Watersheds, Philip Adanbe Adalikwu
Electronic Theses and Dissertations
The increasing application of geographic information system (GIS) technology in watershed modeling makes is necessary to further evaluate its impacts on runoff characteristics as a basis for improved hydrologic analysis in ungauged watersheds. Experts in the field of water resources and hydrology have recommended the practice of subdivision when modeling a watershed, and the use of observed data from hydrologically similar watershed to calibrate and validate an ungauged watershed’s model. However, previous studies have failed to adequately address the issues of watershed heterogeneity, spatial and temporal variability in physical parameters, GIS data resolution issues, including artifacts in automated extraction of …
Monitoring Methods And Performance Assessment For Implementation Of Low Impact Development Practices In South Dakota, Farhana Akhter
Monitoring Methods And Performance Assessment For Implementation Of Low Impact Development Practices In South Dakota, Farhana Akhter
Electronic Theses and Dissertations
Urbanization increases impervious surface area, which changes the hydrology of a watershed. Impervious surfaces prevent the infiltration of stormwater water into the ground surface which results in a higher volume of stormwater runoff and higher peak flow. Low Impact Development (LID) practices help to restore pre-development hydrology by increasing infiltration, evaporation, and transpiration. While the hydrologic performance of LID practices has been studied extensively and continues to be an area of active research, there has been very limited monitoring or demonstration of LID practices in South Dakota. In addition, municipalities in South Dakota and elsewhere that implement new LID practices …
Modeling Response Of Water Quality To Land-Use And Climate Change In Lake Auburn, Me, Nicholas Messina
Modeling Response Of Water Quality To Land-Use And Climate Change In Lake Auburn, Me, Nicholas Messina
Electronic Theses and Dissertations
Lake Auburn, Maine, USA, is a historically unproductive lake that has experienced multiple algal blooms since 2011. The lake is the water supply source for a population of ~60,000. We modeled past temperature, and concentrations of dissolved oxygen (DO) and phosphorus (P) in Lake Auburn by considering the watershed and internal contributions of P as well as atmospheric factors, and predicted the change in lake water quality in response to future climate and land-use changes. A stream hydrology and P-loading model (SimplyP) was used to generate input from two major tributaries into a lake model (MyLake) to simulate physical mixing, …
Perspectives On Water Resources Risk, Policy, And Stewardship, Anne Marie Lausier
Perspectives On Water Resources Risk, Policy, And Stewardship, Anne Marie Lausier
Electronic Theses and Dissertations
Water management approaches have historically optimized water for human use and placed lower emphasis on the relationship between ecosystems and humans. Despite efforts to balance human and ecosystem needs, existing management approaches tend to prioritize some needs, knowledges, and values over others. Natural and anthropogenic changes pose challenges to water governance institutions due to policy inflexibility, and may lead to ecosystem degradation, water stress, and conflict among water users. This work seeks to redress these shortcomings through three scholarly contributions. First, a conceptual framework for Water Resources Stewardship is developed in support of equitable and adaptive solutions under changing conditions. …
Analysis Of Hydrodynamic And Bathymetric Gradients In Canaveral National Seashore Following Living Shoreline And Oyster Restorations, David Spiering
Analysis Of Hydrodynamic And Bathymetric Gradients In Canaveral National Seashore Following Living Shoreline And Oyster Restorations, David Spiering
Electronic Theses and Dissertations
Coastal vulnerability has been gaining recognition as a critical issue, especially with the increasing predictions of sea level rise. Susceptibility to extreme events, eutrophication, and shoreline modification has left many coastal regions in a degraded state. Shoreline protection has traditionally taken the form of seawalls and offshore breakwaters which can be detrimental to both the local ecosystems and adjoining shorelines. The objective of this thesis is to analyze the hydrodynamic and bathymetric variation that occurs within Mosquito Lagoon, Florida following living shoreline and oyster reef restorations. The shoreline sites were sampled using a Before-After-Control-Impact (BACI) design and data were analyzed …
The Effect Of Edge-Of-Field Nutrient Management Practices On Microbial Concentrations In Subsurface Drainage Water And The Associated Risk Of Antibiotic Resistance Dissemination, Sara Mardani
Electronic Theses and Dissertations
Many in-field and edge-of-field management practices have been used to reduce nutrient loads from agricultural fields. The denitrification woodchip bioreactor (WB) is one edgeof- field management practice that has proven to be effective in removing nitrate from subsurface drainage water. The success in nitrate removal achieved with WBs has raised interest in expanding their capabilities for removing other agricultural pollutants, including phosphorus, by using other types of media like phosphorus-sorbing filters or combining these filters with woodchips to remove both nitrate and phosphorus as dual-nutrient removal systems. Despite the extensive research done on WBs and nutrient filter materials, little consideration …
Adsorption Capacity Assessment Of Advance Green Environmental Media To Remove Nutrients From Stormwater-Runoff, Hanan Elhakiem
Adsorption Capacity Assessment Of Advance Green Environmental Media To Remove Nutrients From Stormwater-Runoff, Hanan Elhakiem
Electronic Theses and Dissertations
Best Management Practices (BMPs) in stormwater treatment are a suite of treatment alternatives to deal with pollutant removal problems from stormwater runoff. Biosorption-activated media (BAM) are green sorption media consists of recycled materials have shown excellent nutrient removal as an effective BMP by enhancing physicochemical and microbiological processes. In this study, Iron-Filling Green Environmental Media (denoted as IFGEM-3) and Advanced Green Environmental Media 1 and 2 (denoted as AGEM-1 and AGEM-2) were produced and tested for their adsorption capacities as well as removal and recovery potential for phosphate, nitrate, and ammonia against natural soil (baseline) collected from a stormwater retention …
Natural Sunlight Photodegradation Of Halogenated Disinfection Byproducts In Water, Ibrahim Abusallout
Natural Sunlight Photodegradation Of Halogenated Disinfection Byproducts In Water, Ibrahim Abusallout
Electronic Theses and Dissertations
Disinfection byproducts (DBPs) presence in wastewater effluents and receiving waters may impact the quality of drinking water during water reuse practices. Natural solar photolysis is one of the biogeochemical processes that may lead to decreased DBPs concentrations in water. The purpose of this dissertation is to determine the fate of chlorinated, brominated and iodinated DBPs in surface water by natural sunlight photolysis and investigate the use of solar-based advanced oxidation processes (AOPs) for removal of DBPs in water. Total organic halogen (TOX) was used to measure total chlorinated- (TOCl), brominated- (TOBr) and iodinated-DBPs (TOI) in water. The first objective was …
Assessment Of A Surface Water Supply For Source And Treated Distribution System Quality, Angela Rodriguez
Assessment Of A Surface Water Supply For Source And Treated Distribution System Quality, Angela Rodriguez
Electronic Theses and Dissertations
This study focused on providing a source to tap assessment of surface water systems with respect to (i) the use of alternative biomonitoring tools, (ii) disinfection byproduct (DBP) formation and control, and (iii) corrosion control. In the first study component, two water systems were microbiologically evaluated using adenosine triphosphate (ATP) bioluminescence technology. It was determined that microbial ATP was useful as a surrogate for biomonitoring within a surface water system when paired with traditional methods. Although microbial activity differed between distribution systems that used either chloramine or chlorine disinfectant, in both cases flowrate and season affected microbial ATP values. In …
An Assessment Of Biosorption Activated Media For The Removal Of Pollutants In Up-Flow Stormwater Treatment Systems, Andrew Hood
An Assessment Of Biosorption Activated Media For The Removal Of Pollutants In Up-Flow Stormwater Treatment Systems, Andrew Hood
Electronic Theses and Dissertations
Nitrogen and phosphorus are often the limiting nutrients for marine and freshwater systems respectively. Additionally, stormwater often contains elevated levels of pathogens which can pollute the receiving water body and impact reuse applications [1-4]. The reduction of limiting nutrients and pathogens is a common primary target for stormwater best management practices (BMPs) [5]. Traditional BMPs, such as retention/detention treatment ponds require large footprints and may not be practical in ultra-urban environments where above ground space is limited. Upflow filters utilizing biosorption activated media (BAM) that can be placed underground offer a small footprint alternative. Additionally, BAM upflow filters can be …
Long-Term Carbon And Copper Impact On Nutrient Removal Via Green Sorption Media In Dynamic Linear Ditch Environments, Diana Ordonez
Long-Term Carbon And Copper Impact On Nutrient Removal Via Green Sorption Media In Dynamic Linear Ditch Environments, Diana Ordonez
Electronic Theses and Dissertations
Nutrient-laden stormwater runoff causes environmental and ecological impacts on receiving water bodies. Biosorption Activated Media (BAM) composed of the sand, tire crumb, and clay have been implemented in stormwater best management practices due to its ability to efficiently remove nutrients from stormwater runoff, such as in roadside linear ditches, via unique chemophysical and microbiological processes. In this study, a set of fixed-bed columns were set up to simulate some external forces in roadside linear ditches and examine how these external forces affect the performance of BAM. In our experiment, scenario 1 simulates the impact that animals such as tortoises, moles …
Stream Flow Analysis Of The Big Sioux River Just South Of Brookings, South Dakota, Samuel Ruppert
Stream Flow Analysis Of The Big Sioux River Just South Of Brookings, South Dakota, Samuel Ruppert
Electronic Theses and Dissertations
Floods are the most common type of natural disaster in the world and one of the most damaging. Changes in climate conditions such as precipitation and temperature are causing changes in stream flow. This means that in order to better understand flooding and possibly develop a system for making flood predictions, stream flow needs to be analyzed more closely. The primary objective of this thesis is to analyze the Big Sioux River just south of Brookings, South Dakota, both annually and seasonally. The United States Geological Survey (USGS) has stream gauges placed in rivers and streams all over the United …
Variability Of E. Coli In Streambed Sediments And Its Implication For Water Quality, Sadia Salam
Variability Of E. Coli In Streambed Sediments And Its Implication For Water Quality, Sadia Salam
Electronic Theses and Dissertations
Fecal indicator bacteria (FIB), including E. coli, are the number one cause of water quality impairments in the United States according to the USEPA. FIB are used as a predictor to identify the possible presence of pathogens in waterbodies. E. coli is a useful indicator of gastrointestinal (GI) related illnesses from contact with fresh water. While surface water is routinely monitored for water quality, streambed sediments are rarely considered as a source of FIB to the overlying water column. This study focuses on understanding the variation of E. coli concentrations in streambed sediments and the potential impact of sediment sources …
Application Of Drainage Water Management And Saturated Buffers For Conservation Drainage In South Dakota, Abhinav Sharma
Application Of Drainage Water Management And Saturated Buffers For Conservation Drainage In South Dakota, Abhinav Sharma
Electronic Theses and Dissertations
Edge of field practices such as drainage water management (DWM) and saturated buffers can reduce nutrient transport from croplands to surface waterbodies. DWM uses stackable weir boards in a control structure to manipulate the water table depth throughout the cropping season and reduce the amount of nutrient rich water draining out from the field. Saturated buffers, on the other hand, use a control structure to divert water draining out from the cropland to a vegetative strip via a subsurface tile installed parallel to a waterway. For the saturated buffer systems, a combination of natural denitrification, nitrogen mineralization, and plant uptake …
Evaluating E. Coli Particle Attachment And The Impact On Transport During High Flows, Louis Amegbletor
Evaluating E. Coli Particle Attachment And The Impact On Transport During High Flows, Louis Amegbletor
Electronic Theses and Dissertations
Fecal indicator bacteria, including E. coli, are the leading cause of water quality impairments within assessed waters in the United States. The source of E. coli includes WWTP, leaking sewers, animal manure, wildlife, livestock, and stream bed sediment. Storm events contribute to bacteria loading within waters through wash-in of land sources of bacteria and resuspension of bacteria within sediments. Bacteria introduced into the water column are either attached to particles or are unattached (or free-living). The goal of this study was to examine the attachment of E. coli to different particle sizes, including their impact on contributing to water …
A Development Of Travel Time Equation For Overland Flow As Affected By Vegetation, Naga Vara Prasad Ganti
A Development Of Travel Time Equation For Overland Flow As Affected By Vegetation, Naga Vara Prasad Ganti
Electronic Theses and Dissertations
In overland flow water research, travel time is a significant parameter used in estimating peak discharge in channels or rivers. Overland flow is assumed to be in turbulent condition to estimate travel time using Manning’s Velocity Equation (MVE). When the flow is in a laminar condition, Grismer’s Laminar Mean Velocity Equation (GLMVE) is applied but fails to consider the roughness parameter. A review of the literature shows numerous equations for overland travel time, but there is no known equation that determines the mean velocity of overland flow under laminar condition with a roughness coefficient or other coefficient related to the …
Comparison Of Historical Precipitation For Aberdeen, Ipswich, And Eureka, South Dakota, Uday Singh Kshatriya
Comparison Of Historical Precipitation For Aberdeen, Ipswich, And Eureka, South Dakota, Uday Singh Kshatriya
Electronic Theses and Dissertations
The availability of water resources varies from time to time with the climate conditions. Keeping track of climate conditions would eventually benefit for the future predictions. The objective of this research was to compare and contrast the climate especially for Aberdeen, Ipswich and Eureka, South Dakota utilizing the historical monthly precipitation records and to develop the techniques that are reliable to estimate the missing data. For these necessary statistical analyses were performed using the monthly precipitation data from High Plains Regional Climate Center (HPRCC) for the annual and 8-Year periods for Aberdeen, Ipswich and Eureka, South Dakota. 63 water years …
Modeling Water Availability, Risk And Resilience In A Semi-Arid Basin In Southern Africa, Esther N. Mosase
Modeling Water Availability, Risk And Resilience In A Semi-Arid Basin In Southern Africa, Esther N. Mosase
Electronic Theses and Dissertations
Climate variability need to be incorporated into the management and planning of water resources, particularly in arid and semi-arid regions, where water availability is more sensitive to rainfall and air temperature. This study used modified Man-Kendall trend analysis test and ArcGIS to process data. Annual means of rainfall, minimum temperature and maximum temperature in the Limpopo River Basin (LRB) varied between 160 and 1109 mm, 8 °C to 20 °C and 23 °C to 32 °C respectively. The spatial pattern is generally increasing from west to east for rainfall and minimum temperature while maximum temperature increases from south to north …
Water Chemistry Dynamics In Four Vernal Pools In Maine, Usa, Lydia H. Kifner
Water Chemistry Dynamics In Four Vernal Pools In Maine, Usa, Lydia H. Kifner
Electronic Theses and Dissertations
Vernal pools are small seasonal wetlands that are a common landscape feature that contribute to biodiversity in northeastern North American forests. However, even basic information about their biogeochemical functions, such as carbon cycling, is limited. Dissolved gas concentrations (CH4, CO2) and other water chemistry parameters were monitored weekly at the bottom and surface of four vernal pools in central and eastern Maine, USA, from April to August 2016. The vernal pools were supersaturated with respect to CH4 and CO2 at all sampling dates and locations. Concentrations of dissolved CH4 and CO2 ranged …
Ichetucknee Springs: Measuring The Effects Of Visitors On Water Quality Parameters Through Continuous Monitoring., Sarah Faraji
Ichetucknee Springs: Measuring The Effects Of Visitors On Water Quality Parameters Through Continuous Monitoring., Sarah Faraji
Electronic Theses and Dissertations
Ichetucknee Springs System is in north central Florida, under the jurisdiction of the Suwannee River Water Management District (SRWMD). The Ichetucknee River is one of the most pristine spring-fed rivers in Florida and became a state park in 1970. Over 400,000 people visited the Ichetucknee Springs State Park in 2016. From that total, over 130,000 people came during the tubing season alone (Memorial Day to Labor Day). During the tubing season, only 750 visitors per day are allowed to launch from the North Launch, near the Ichetucknee Head Spring. The park enforces visitor usage of the river during these time …
Groundwater Modeling For Assessing The Impacts Of Natural Hazards In East-Central Florida, Han Xiao
Groundwater Modeling For Assessing The Impacts Of Natural Hazards In East-Central Florida, Han Xiao
Electronic Theses and Dissertations
In coastal east-central Florida (ECF) , the low-lying coastal alluvial plains and barrier islands have a high risk of being inundated by seawater due to climate change effects such as sea-level rise, changing rainfall patterns, and intensified storm surge from hurricanes., This will produce saltwater intrusion into the coastal aquifer from infiltration of overtopping saltwater. In the inland ECF region, sinkhole occurrence is recognized as the primary geologic hazard causing massive financial losses to society in the past several decades. The objectives of this dissertation are to: (1) evaluate the impacts of sea-level rise and intensified storm surge on the …
Assessing Interactions Between Estuary Water Quality And Terrestrial Land Cover In Hurricane Events With Multi-Sensor Remote Sensing, Chandan Mostafiz
Assessing Interactions Between Estuary Water Quality And Terrestrial Land Cover In Hurricane Events With Multi-Sensor Remote Sensing, Chandan Mostafiz
Electronic Theses and Dissertations
Estuaries are environmentally, ecologically and environmentally important places as they act as a meeting place for land, freshwater and marine ecosystems. They are also called nurseries of the sea as they often provide nesting and feeding habitats for many aquatic plants and animals. These estuaries also withstand the worst of some natural disasters, especially hurricanes. The estuaries as well as the harbored ecosystems undergo significant changes in terms of water quality, vegetation cover etc. and these components are interrelated. When hurricane makes landfall it is necessary to assess the damages as quickly as possible as restoration and recovery processes are …
Using Remote Sensing To Estimate Crop Water Use To Improve Irrigation Water Management, Arturo Reyes-Gonzalez
Using Remote Sensing To Estimate Crop Water Use To Improve Irrigation Water Management, Arturo Reyes-Gonzalez
Electronic Theses and Dissertations
Irrigation water is scarce. Hence, accurate estimation of crop water use is necessary for proper irrigation managements and water conservation. Satellite-based remote sensing is a tool that can estimate crop water use efficiently. Several models have been developed to estimate crop water requirement or actual evapotranspiration (ETa) using remote sensing. One of them is the Mapping EvapoTranspiration at High Resolution using Internalized Calibration (METRIC) model. This model has been compared with other methods for ET estimations including weighing lysimeters, pan evaporation, Bowen Ratio Energy Balance System (BREBS), Eddy Covariance (EC), and sap flow. However, comparison of METRIC model outputs to …
Modeling Streamflow And Water Quality Impacts Of Grassland Establishment, Conversion, And Management In Skunk Creek Watershed, Jiyeong Hong
Modeling Streamflow And Water Quality Impacts Of Grassland Establishment, Conversion, And Management In Skunk Creek Watershed, Jiyeong Hong
Electronic Theses and Dissertations
Grassland is a valuable natural resource with many environmental benefits, which include erosion control, wildlife habitat promotion, water quality protection, and flood prevention. Conversion of grassland to cultivated cropland has been linked to environmental quality concerns. The goal of this study was to model the impacts of grassland establishment, depletion, and management on hydrology and water quality in Skunk Creek watershed in eastern South Dakota. The specific objectives are to quantify the impacts of grassland conversion and selected management regimes on streamflow and water quality, and explore the optimum grassland establishment location within a watershed to achieve water quality benefits. …
A Demonstration Study Of Drainage Water Management In Eastern South Dakota, Ashik Sahani
A Demonstration Study Of Drainage Water Management In Eastern South Dakota, Ashik Sahani
Electronic Theses and Dissertations
Subsurface drainage is a common water management practice for improving crop production in poorly drained soils; however, the practice is associated with several environmental concerns such as nutrient losses to downstream surface waters. These environmental concerns from subsurface drainage have prompted interest in drainage water management strategies such as controlled drainage. This study assessed the agronomic and environmental impacts of drainage water management in eastern South Dakota by using two demonstration plots for controlled and conventional drainage. Drain flow, nitrate and dissolved phosphorous concentration in drain water, shallow groundwater, crop yield, residual soil nitrate, soil moisture and temperature, soil penetration …