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Hydrology

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Full-Text Articles in Physical Sciences and Mathematics

Water Quality Responses To A Semi-Arid Beaver Meadow In Boise, Idaho, Luise Bayer Winslow Dec 2021

Water Quality Responses To A Semi-Arid Beaver Meadow In Boise, Idaho, Luise Bayer Winslow

Boise State University Theses and Dissertations

Beavers have been instrumental in shaping the North American riverine landscape. However, land use change and beaver trapping have caused large decreases in beaver populations, resulting in fundamental changes to river morphology, hydrology, and biogeochemical function. Effective river restoration and remediation of arid western rivers relies on a comprehensive interpretation of how beaver activity influences water quantity and quality. In this study, I compared two stream reaches with and without beaver dams in a semi-arid watershed, to quantify the effects of beaver activity on hydrology and biogeochemistry. Within each reach, I combined dilution gauging and stream tracer experiments to determine …


Testing The Impact Of A Freshwater Wetland Restoration On Water Table Elevation And Soil Moisture Using A Parametric Groundwater Modeling Approach, Erika T. Ito Oct 2021

Testing The Impact Of A Freshwater Wetland Restoration On Water Table Elevation And Soil Moisture Using A Parametric Groundwater Modeling Approach, Erika T. Ito

Masters Theses

Wetlands are now recognized for the many social, environmental, ecological, and economic benefits they provide. They improve water quality, support biodiversity, abate floods and storms, and provide local recreational areas. Historically, many wetlands have been drained or altered for residential, commercial, or agricultural use. Effective wetland restoration projects reestablish ecosystem services and mitigate legacy effects of land use change to create self-sustaining systems. However, a persisting lack of scientifically-vetted methodological and evaluation guidelines in the field of restoration ecology has caused many restoration efforts to fail to restore natural wetland hydrologic conditions. By definition, wetlands must be saturated, permanently or …


Spatiotemporal Variability Of Soil Water Δ18o And Δ2h Reveals Hydrological Processes In Two Floodplain Soils, Amanda Ceming-Barbato Sep 2021

Spatiotemporal Variability Of Soil Water Δ18o And Δ2h Reveals Hydrological Processes In Two Floodplain Soils, Amanda Ceming-Barbato

LSU Master's Theses

The movement of water through soil is preferential and heterogeneous. Subsurface interactions between mobile flows and the soil matrix are not uniform and are therefore difficult to predict through time and space. The use of stable isotopes of hydrogen (2H) and oxygen (18O) as conservative tracers of water movement is improving understanding of soil hydrological processes, yet field-scale observations of isotopic variability remain scarce despite implications for identifying dominant hydrologic processes. We sampled two adjacent soils at a ridge-swale topography floodplain forest to determine soil water isotopic variability at a 20 cm depth resolution in soils …


Laboratory Measurement Of Electrical And Hydraulic Properties Of Regolith Over Granitic Bedrock, Taylor James Bienvenue Aug 2021

Laboratory Measurement Of Electrical And Hydraulic Properties Of Regolith Over Granitic Bedrock, Taylor James Bienvenue

Boise State University Theses and Dissertations

Characterizing water flux within the critical zone (CZ) is essential for a multitude of studies and applications related to irrigation, drainage, water management, and contaminant transport. Trying to measure water flux in the critical zone, specifically in the subsurface, is difficult due to the associated structural heterogeneity and complex interactions taking place between biological, chemical, and physical processes. Current methods (i.e., inferred from soil suction and soil moisture measurements) to characterize water flux within the critical zone can be time consuming and are not directly related to water flux. Recent literature has provided evidence that self-potential (SP) is a promising …


Groundwater Flow And Transport At The Forest-Marsh Boundary: A Modeling Study, Sophia Chason Sanders Jul 2021

Groundwater Flow And Transport At The Forest-Marsh Boundary: A Modeling Study, Sophia Chason Sanders

Theses and Dissertations

The forest-marsh boundary, where tidally influenced salt marshes meet a forested upland, is hydrologically complex due to its multiple water inputs. Groundwater flow and salinity transport at this boundary are not well understood. In order to make predictions about salinity at this boundary as it responds to climatic factors, a two-dimensional model was built to simulate groundwater flow and solute transport at a salt marsh on Sapelo Island, Georgia. After calibration based on observed data from wells at the study site, the model can be used to identify patterns in groundwater movement and solute transport that may influence the vegetation …


Smallmouth Bass Feeding Dynamics And Growth In Headwater Streams Of The Interior Highlands, Brandon C. Plunkett May 2021

Smallmouth Bass Feeding Dynamics And Growth In Headwater Streams Of The Interior Highlands, Brandon C. Plunkett

ATU Theses and Dissertations 2021 - Present

Smallmouth Bass have been extensively studied, but knowledge of the effects of temperature and hydrologic regime on populations in the Interior Highlands of Arkansas remains lacking. In 2018, I monitored diet characteristics of Smallmouth Bass, located in streams prone to dryness and representing a range of water temperatures, and presence of potential competitors. Diet characteristics of Smallmouth Bass, Green Sunfish, and Creek Chub were studied in the Boston Mountains ecoregion of Arkansas during the summer of 2018. In 2019, I expanded the scope of the project to search for relationships between Smallmouth Bass growth and hydrologic regime. My objectives were …


Using Low-Flow Sampling Data To Estimate Hydraulic Conductivity In Aquifers, Joy Kiefer May 2021

Using Low-Flow Sampling Data To Estimate Hydraulic Conductivity In Aquifers, Joy Kiefer

Masters Theses

Hydrogeologists sample wells to test aquifer water quality and use slug tests to estimate aquifer permeability. Robbins et al. (2009) proposed a more efficient way to obtain the goals of the two tests—the use of low-flow sampling and the use of the resulting flow rate and drawdown data to estimate aquifer hydraulic conductivity (K). The Robbins et al. method calculates K by using the slope of the best fit line from the graph of flow rate vs. drawdown for all low-flow pumping data collected at a well. When the method was applied to low-flow data from four Kalamazoo, MI, it …


Using Remote Sensing Data Fusion Modeling To Track Seasonal Snow Cover In A Mountain Watershed, Allison N. Vincent May 2021

Using Remote Sensing Data Fusion Modeling To Track Seasonal Snow Cover In A Mountain Watershed, Allison N. Vincent

Boise State University Theses and Dissertations

Seasonal snowfall is the largest component of the water budget in many mountain headwater regions around the world. In addition to sustaining biological water needs in drier, lower elevation areas throughout the year, mountain snowpack also provides essential water inputs to the Critical Zone (CZ) - the outer layer of the Earth’s surface, which hosts a variety of biogeochemical processes responsible for transforming inorganic matter into forms usable for life. Water is a known driver of CZ activity, but uncertainty exists in its spatial and temporal interactions with CZ processes, particularly in the complex terrain of heterogeneous mountain areas. Increasing …


Characterization Of Problematic Red Clay Soils In Arkansas For The Purpose Of Onsite Wastewater System Placement, Bailey Darnell May 2021

Characterization Of Problematic Red Clay Soils In Arkansas For The Purpose Of Onsite Wastewater System Placement, Bailey Darnell

Graduate Theses and Dissertations

Distinguishing between red-clay soils that are non-expansive and can reduce and red-clay soils developing in problematic red parent material, which are expansive, but also non-reducing, is key for proper on-site wastewater system placement. The Arkansas Department of Health allows for the placement of on-site wastewater systems in certain red-clay soils that have the potential to reduce, but only in the Ozark Highlands [Major Land Resource Area (MLRA) 116A], which is referred to as the red-soil exception. There is currently little scientific data to support the geographic restriction of the red-soil exception. The objectives of this study were to: i) confirm …


Quantifying The Impacts Of Land Use, Management And Climate Change On Water Resources In Missouri River Basin, Arun Bawa Jan 2021

Quantifying The Impacts Of Land Use, Management And Climate Change On Water Resources In Missouri River Basin, Arun Bawa

Electronic Theses and Dissertations

A location-specific evaluation of hydrological landscape responses concerning past and projected climate and land use land cover (LULC) changes can provide a powerful intellectual basis for developing efficient and profitable agroecosystems, and overcoming uncertain and detrimental consequences of LULC and climate shifts. This dissertation assessed the impacts of land use, management, and climate change on water resources in the Missouri River Basin (MRB) through four specific studies that included: (i) to study the responses of leached nutrient concentrations and soil health to winter rye cover crop (CC) under no-till corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotation, (ii) to …


Analysis Of Uncertainty In Hydrometeorological Ensemble Forecasts, Carolien N. Mossel Jan 2021

Analysis Of Uncertainty In Hydrometeorological Ensemble Forecasts, Carolien N. Mossel

Dissertations and Theses

Ensemble hydrometeorological forecasting has great potential for improving flood predictions and use in water management systems, however, the amount of data used and created with an ensemble forecast requires a careful and intentional approach to understand how useful and skillful the forecast is. The NOAA National Water Model (NWM) was run using downscaled NOAA Global Ensemble Forecast System (GEFS) meteorological forcings for the 2016-2017 wet season (October-March) in California to create an 11-member hydrologic forecast ensemble. To evaluate the performance of these ensemble forecasts, we chose to study streamflow sites within Sonoma County, California, a rain-dominated region which includes the …


Relating Streamflow Discharge To Surface Elastic Response Under Hydrologic Loading Using Single Gps Vertical Displacement And The Storage-Discharge Relationship At Local Watershed Scales, Noah B. Clayton Jan 2021

Relating Streamflow Discharge To Surface Elastic Response Under Hydrologic Loading Using Single Gps Vertical Displacement And The Storage-Discharge Relationship At Local Watershed Scales, Noah B. Clayton

Graduate Student Theses, Dissertations, & Professional Papers

Uncertainties associated with climate change and increasing demands for water resources require better methods for estimating water availability at small to intermediate watershed scales (<1500 km2). Temporal changes in watershed storage and transport across various watersheds in the western U.S. were investigated using the hydrologic loading signal from GPS vertical displacements as a proxy for changes in watershed total terrestrial storage. GPS vertical displacement and streamflow discharge relationships were analyzed at daily to monthly temporal resolution. Stream connected storage changes were inferred using discharge using a first-order dynamical system model. Storage inferred from discharge, GPS vertical displacement and storage …


An Analysis Of River Channel Change Over Time In The Lamprey River, Trevor R. Fenoff Jan 2021

An Analysis Of River Channel Change Over Time In The Lamprey River, Trevor R. Fenoff

Honors Theses and Capstones

Flooding causes river channel change that threatens people and property. Due to climate change and urbanization, flooding events are projected to happen more frequently in the future, which will make the associated hazards worse. This project estimated the historical river channel change in the Lamprey River in southern New Hampshire. River channel change was estimated by delineating riverbank location on historical aerial photographs. The river channel change was compared to river width, curvature, and the number of 1.5-year flood events to explore the drivers of river channel change in the Lamprey River.


Understanding The Effect Of Climate And Hydrometeorological Extremes On Natural And Human-Induced Hydrosystems, Jeongwoo Hwang Jan 2021

Understanding The Effect Of Climate And Hydrometeorological Extremes On Natural And Human-Induced Hydrosystems, Jeongwoo Hwang

Dissertations and Theses

The contemporary hydrosystems of the United States involve a complex combination of natural and modified basins in the presence of changing climate and anthropogenic impacts. An enhanced understanding of the interdependence between climate forcings, human-induced interventions, and water balance in both natural and modified basins are essential for developing reliable and resilient hydrosystems and for better water resources management. In response, this dissertation focuses on investigating the hydroclimatology of natural and modified basins across the contiguous United States. It has three research objectives: (1) to explain flow alterations due to anthropogenic activities, especially dam operations, in modified basins and understand …


Grain-Size And Permeability Of Sediments Within The Hyporheic Zone At The Theis Environmental Monitoring And Modeling Site, Great Miami River And Buried Valley Aquifer, Southwest Ohio, Usa, Timothy Wayne Cornett Jan 2021

Grain-Size And Permeability Of Sediments Within The Hyporheic Zone At The Theis Environmental Monitoring And Modeling Site, Great Miami River And Buried Valley Aquifer, Southwest Ohio, Usa, Timothy Wayne Cornett

Browse all Theses and Dissertations

The Theis Environmental Monitoring and Modeling Site is a field research facility, located on the Great Miami River in southwest Ohio, dedicated to the study of hyporheic zone processes. The site is underlain by an aquifer on the order of 21 meters thick, comprised of fluvial deposits. The permeability of the aquifer sediments was quantified both from one large scale hydraulic test (~100 m radial distance) and from grain-size analysis of 119 small-scale core samples (~20 cm length each). The permeability determined from the large-scale hydraulic test is 98.9 Darcies. The test also gave a value for specific yield of …


Grain-Size And Permeability Of Sediments Within The Hyporheic Zone At The Theis Environmental Monitoring And Modeling Site, Great Miami River And Buried Valley Aquifer, Southwest Ohio, Usa, Timothy Wayne Cornett Jan 2021

Grain-Size And Permeability Of Sediments Within The Hyporheic Zone At The Theis Environmental Monitoring And Modeling Site, Great Miami River And Buried Valley Aquifer, Southwest Ohio, Usa, Timothy Wayne Cornett

Browse all Theses and Dissertations

The Theis Environmental Monitoring and Modeling Site is a field research facility, located on the Great Miami River in southwest Ohio, dedicated to the study of hyporheic zone processes. The site is underlain by an aquifer on the order of 21 meters thick, comprised of fluvial deposits. The permeability of the aquifer sediments was quantified both from one large scale hydraulic test (~100 m radial distance) and from grain-size analysis of 119 small-scale core samples (~20 cm length each). The permeability determined from the large-scale hydraulic test is 98.9 Darcies. The test also gave a value for specific yield of …


Hydrologic Investigation Of The Chiwaukee Prairie (Wisconsin) Restoration, Nick Potter Jan 2021

Hydrologic Investigation Of The Chiwaukee Prairie (Wisconsin) Restoration, Nick Potter

Dissertations, Master's Theses and Master's Reports

Wetlands are a vital component of the landscape, a keystone ecosystem, that are prone to degradation and destruction with urbanization. As a result, significant efforts from communities, scientists, sportsmen and government agencies have been made to protect and restore wetlands. In 2019, The Nature Conservancy began re-wetting, contouring, and seeding a 55-ha parcel of farmland in Pleasant Prairie, Wisconsin, restoring the site in an attempt to resemble pre-settlement conditions. The Nature Conservancy Restoration site is part of the groundwater recharge zone of Chiwaukee Prairie and its restoration aimed to increase the available groundwater for adjacent Chiwaukee Prairie State Natural Area …


Regional Impacts Of Invasive Species And Climate Change On Black Ash Wetlands, Joseph Shannon Jan 2021

Regional Impacts Of Invasive Species And Climate Change On Black Ash Wetlands, Joseph Shannon

Dissertations, Master's Theses and Master's Reports

For more than a decade intensive research on the ecohydrology of black ash wetland ecosystems has been performed to understand these systems before they are drastically altered by the invasive species, emerald ash borer (EAB). In that time there has been little research aimed at the scale and persistence of the alterations. Three distinct but related research articles will be presented to demonstrate a method for moderate resolution mapping of black ash across its entire range, understand the relative impacts of EAB and climate change on probable future wetland conditions, and develop an experimental and modeling approach to quantify and …


Spatiotemporal Patterns In Water Yield From The Humid Puna: A Case Study In The Agrarian District Of Zurite, Perú, Wyeth Wunderlich Jan 2021

Spatiotemporal Patterns In Water Yield From The Humid Puna: A Case Study In The Agrarian District Of Zurite, Perú, Wyeth Wunderlich

Cal Poly Humboldt theses and projects

The humid puna is a seasonally dry alpine grass- and shrub-land biome that exists at the altitudinal limits of plant survival, hosts peat-forming wetlands known as bofedales, and yields water to streams used by small and large communities throughout the central and southern Peruvian Andes. Despite the importance of the humid puna in supplying water resources, particularly to perennial streams, few studies have quantified water yield and no studies have explored relationships between the structure of puna landscapes and spatial patterns in water yield. Zurite (population: 3,640, elevation: 3,011 m.a.s.l., annual precipitation: 855 mm) is an agrarian district in …


Nitrogen Dynamics And Transport Along Flowpaths In A Rural Wetland-Stream Complex, Colton Kyro Jan 2021

Nitrogen Dynamics And Transport Along Flowpaths In A Rural Wetland-Stream Complex, Colton Kyro

Graduate Student Theses, Dissertations, & Professional Papers

Human activities have doubled the rate of nitrogen inputs onto the landscape resulting in elevated nitrogen concentrations in our streams. Anthropogenically applied nitrogen is largely transported to stream networks via groundwater movement. Groundwater discharge occurs in distinct points along a stream but whose influences can often persist far beyond that area due to insufficient biogeochemical removal of imported nitrogen potentially causing alterations in community structure and precipitating large algae blooms. To understand the factors governing nitrogen abundance in a historical polluted stream, I used a mass-balance approach to quantify groundwater-surface water interaction and the magnitude of groundwater nitrogen input and …


The Impact Of Stream-Groundwater Exchange On Seasonal Nitrate Loads In An Urban Stream, Julio I. Beltran Aug 2020

The Impact Of Stream-Groundwater Exchange On Seasonal Nitrate Loads In An Urban Stream, Julio I. Beltran

Theses - ALL

Urbanization negatively impacts water quality in streams by reducing stream-groundwater interactions, which reduces the stream’s ability to naturally attenuate nitrate. Meadowbrook Creek, a first order urban stream in Syracuse, New York, has a negative urbanization gradient that results in urbanized headwaters that are disconnected from the floodplain, and downstream reaches that have intact riparian floodplains and connection to riparian aquifers. This system allows us to assess how stream-aquifer interactions in urban streams impact the net sources and sinks of nitrate at the reach scale. We used continuous (15-minute) streamflow measurements, along with weekly grab samples at three gauging stations positioned …


High-Resolution Timeseries Analysis Of Dynamic Geochemistry: A 27-Well Survey Of Contaminated Groundwater Downstream Of The Former S-3 Ponds, Oak Ridge, Tennessee, Emma Dixon Aug 2020

High-Resolution Timeseries Analysis Of Dynamic Geochemistry: A 27-Well Survey Of Contaminated Groundwater Downstream Of The Former S-3 Ponds, Oak Ridge, Tennessee, Emma Dixon

Masters Theses

Spatiotemporal variability of geochemistry of contaminated groundwater has large implications on overall water quality and ability to respond to remedial applications. Gaining knowledge of how geochemistry changes over time in an area can help establish response trends to changing external conditions like weather and level of contamination. In this study, a spatiotemporal survey was performed on 27 wells at the Y-12 Complex in Oak Ridge, Tennessee. This was completed to measure diurnal fluxes in geochemistry from seasonal changes and extreme weather conditions in three areas of historically different contamination levels from a single point contamination source. Measurements were gathered over …


Paleoenvironmental Reconstruction Of Quaternary Saltville, Virginia, Using Ostracode Autecology, Austin Gause Aug 2020

Paleoenvironmental Reconstruction Of Quaternary Saltville, Virginia, Using Ostracode Autecology, Austin Gause

Electronic Theses and Dissertations

The Saltville valley in southwestern Virginia is home to Quaternary localities containing paleontological and archaeological remains. Historically the valley has been mined for salt and the small lakes, ponds and springs along the valley floor have a brackish signature. A preliminary report on the site’s ostracode fauna suggested that the site’s water was not always saline. This study analyzed modern and Quaternary ostracodes to understand the valley’s hydrologic and chemical evolution. Sediments contained primarily freshwater species, including the environmentally sensitive Candona crogmaniana. The presence of Pelocypris tuberculatum and a new Fabaeformiscandona species throughout a vertical section spanning the latest Pleistocene …


Fluvial Geomorphic And Hydrologic Evolution And Climate Change Resilience In Young Volcanic Landscapes: Rhyolite Plateau And Lamar Valley, Yellowstone National Park, Benjamin Newell Burnett Jul 2020

Fluvial Geomorphic And Hydrologic Evolution And Climate Change Resilience In Young Volcanic Landscapes: Rhyolite Plateau And Lamar Valley, Yellowstone National Park, Benjamin Newell Burnett

Earth and Planetary Sciences ETDs

Quaternary volcanism associated with the last caldera cycle in Yellowstone National Park included emplacement of ash-flow tuffs, massive rhyolite flows ranging from 79 to 484 ka, and valley-filling basalts. This study examines (1) the evolution of spring hydrology with flow age on the Rhyolite Plateau, (2) initial development and evolution of stream networks on the rhyolite flows, and (3) the impact of the 630 ka caldera formation and volcanic flow emplacement on Lamar Valley incision rates.

Integrated stream networks formed within 79 kyr on the Rhyolite Plateau. Incision is focused on steep flow margins and knickpoints and is dependent on …


Exploring The Potential Of Nutrient Retention And Recycling With Wetlaculture Systems In Ohio With Physical And Landscape Models, Bingbing Jiang Jun 2020

Exploring The Potential Of Nutrient Retention And Recycling With Wetlaculture Systems In Ohio With Physical And Landscape Models, Bingbing Jiang

USF Tampa Graduate Theses and Dissertations

Significant expansion of agricultural land use has been widely recognized for leading to global and regional negative environmental impacts, especially increased eutrophication of surface water systems for the last half-century. The landscape-scale environmental problem of overloading nutrients to lakes and streams by excessive fertilizer use and increased human-caused N-fixation is in urgent need of a sustainable landscape-scale solution. Wetlands have long been considered as an effective way to remove nutrients from surface water. However, the influence of regional seasonality and hydrologic conditions on agricultural runoff treatment wetlands still needs more investigation. A new approach, “wetlaculture,” has recently described as a …


Compound Flooding In Coastal Areas Emanating From Inland And Offshore Events, Hamed Behzad Koochaksaraii May 2020

Compound Flooding In Coastal Areas Emanating From Inland And Offshore Events, Hamed Behzad Koochaksaraii

Dissertations

The vulnerability of urban populations to natural hazards and climate change is a major theme in many reports on coastal cities with flooding ranking highly among the climate change concerns. Flooding could occur as a result of runoff for inland rainfall that accumulates at the mouth of the estuary to the sea or it could occur due to a storm surge emanating from the ocean. The techniques for modeling the flooding from these events are very different, as they were developed in different scientific fields: hydrology and hydraulic engineering for inland rainfall versus coastal oceanography and coastal engineering for offshore …


Protean Caves And Cyrenean Grottos: The Subterranean World Of Vergil's Fourth Georgic, Kirby Schoephoerster May 2020

Protean Caves And Cyrenean Grottos: The Subterranean World Of Vergil's Fourth Georgic, Kirby Schoephoerster

Arts & Sciences Electronic Theses and Dissertations

Using the studies and methodologies spearheaded by the burgeoning field of geomythology, this project aims to reevaluate one of the most famous works of ancient literature, the Georgics of Vergil, within the context of karst geology. In other words, I plan to critically investigate the famous myth of Aristaeus using a geomythological lens that focuses on how Vergil treats caves and cave systems as related to (his) myth. The didactic poem as a whole, and much less so the myth of Aristaeus, has been assessed relatively little by archaeologists, and by geomythologists not at all. Yet, book four contains an …


Changes In Land Use Land Cover (Lulc), Surface Water Quality And Modelling Surface Discharge In Beaver Creek Watershed, Northeast Tennessee And Southwest Virginia, Tosin James May 2020

Changes In Land Use Land Cover (Lulc), Surface Water Quality And Modelling Surface Discharge In Beaver Creek Watershed, Northeast Tennessee And Southwest Virginia, Tosin James

Electronic Theses and Dissertations

Beaver Creek is an impaired streams that is not supporting its designated use for recreation due to Escherichia coli (E.coli), and sediment. To address this problem, this thesis was divided into two studies.

The first study explored changes in Land Use Land Cover (LULC), and its impact on surface water quality. Changes in E.coli load between 1997-2001 and 2014-2018 were analyzed. Also, Landsat data of 2001, and 2018 were examined in Terrset 18.31. Mann-Whitney test only showed a significant reduction in E.coli for one site. Negative correlation was established between E.coli load, and Developed LULC, Forest LULC, and …


Physical And Biological Factors Controlling The Fate Of Nitrate In A Louisiana Coastal Deltaic Floodplain, Alexandra Christensen Apr 2020

Physical And Biological Factors Controlling The Fate Of Nitrate In A Louisiana Coastal Deltaic Floodplain, Alexandra Christensen

LSU Doctoral Dissertations

The Mississippi River Delta is threatened by a growing pressure to support large human populations in the United States both with food production, navigation systems, and urban development in the Mississippi River Basin. Nitrate-nitrogen load in the Mississippi River, up to 100 Tg N yr-1 from agricultural and urban runoff, leads to phytoplankton blooms and hypoxia across the Louisiana continental shelf, creating dead zones of low dissolved oxygen threatening a significant commercial fishery. Along the coast and river corridors, floodplain ecosystems have the capacity to retain and remove nitrate. This dissertation explores the role of productive, actively growing coastal …


Tidal-Groundwater Study Of The Slaughter Beach Salt Marsh In Slaughter Beach, De, Michael Powers Jan 2020

Tidal-Groundwater Study Of The Slaughter Beach Salt Marsh In Slaughter Beach, De, Michael Powers

West Chester University Master’s Theses

Seasonal and decadal monitoring of salt marsh at Slaughter Beach, DE documented long-term and short-term variations in number and sizes of salt ponds. Over 400 salt ponds ranging in size between 0.5 m2 to 0.11 km2 were identified on 5.5 km2 salt marsh platform. The purpose of this study is to quantify hydrologic conditions and measure groundwater discharge of a salt marsh, particularly the impact of tidal forces on groundwater fluctuation.

Four wells with nests of mini-piezometers with ONSET Pressure Transducers were installed along a transect crossing the largest salt pond (0.11 km2) in the …