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Estuary

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Full-Text Articles in Life Sciences

Response Of Fish Assemblages To Increased Connectivity And Habitat Restoration In Bayou St. John, A Degraded Waterway In New Orleans, La, Alia Jones May 2024

Response Of Fish Assemblages To Increased Connectivity And Habitat Restoration In Bayou St. John, A Degraded Waterway In New Orleans, La, Alia Jones

University of New Orleans Theses and Dissertations

Bayou St. John is a degraded waterway located within the City of New Orleans. The Bayou, which is disconnected from Lake Pontchartrain by floodgates, has undergone restoration efforts to improve connectivity through frequent floodgate openings and marsh habitat restoration outside of the floodgates. To assess possible responses of local fish assemblages to these restoration efforts, I analyzed long-term fish assemblage data from three sites located inside of the floodgates and one site located at the restored marsh outside of the floodgates. Two sites inside of the floodgates experienced significant changes in assemblages between the pre-opening period (2006-2012) and post-opening period …


Using Podcasts To Bring National Estuarine Research Reserves Into The Classroom For Grades 6-12, Kaitlyn M. Dirr Apr 2023

Using Podcasts To Bring National Estuarine Research Reserves Into The Classroom For Grades 6-12, Kaitlyn M. Dirr

Senior Theses

In a typical classroom setting, there are significant challenges to exposing students to concepts related to earth sciences and the environment. These challenges are exacerbated when conveying lessons about geographic areas with limited access, such as oceans and coastlines (Louv, 2010). It is now more important than ever for environmental education to improve and adapt to our changing world. Educators may have the opportunity to bring these subjects to life by using media content such as podcasts to introduce students to new places and the scientists, managers and educators that work in those spaces. In the United States, there exists …


Field Assessment Of The Pervious Oyster Shell Habitat: Enhancement Of Intertidal Habitat For The Eastern Oyster And Associated Nekton In Northeast Florida, Hunter Mathews Jan 2023

Field Assessment Of The Pervious Oyster Shell Habitat: Enhancement Of Intertidal Habitat For The Eastern Oyster And Associated Nekton In Northeast Florida, Hunter Mathews

UNF Graduate Theses and Dissertations

A dramatic global decline in oyster reef habitat has led to widespread deployment of oyster restoration projects. Efforts are underway to move away from polluting methods like plastic mesh bags in oyster deployments. Additionally, increasing pressure on our estuaries from recreational boat wakes and intensified storms requires more robust structures for shoreline protection. The “Pervious Oyster Shell Habitat” (POSH) is a novel artificial reef structure composed of oyster shell bound by a thin layer of Portland cement, into the shape of a dome. The structure’s makeup greatly reduces its environmental impact, while providing quality substrate for provision of oyster reef …


Survival And Growth Of Juvenile Coho Salmon (Oncorhynchus Kisutch) In Restored Wetlands Of Humboldt Bay, California, Josh D. Cahill Jan 2023

Survival And Growth Of Juvenile Coho Salmon (Oncorhynchus Kisutch) In Restored Wetlands Of Humboldt Bay, California, Josh D. Cahill

Cal Poly Humboldt theses and projects

Substantial investment in habitat restoration efforts have been made to promote coho salmon (Oncorhynchus kisutch) recovery, yet sampling efforts to document the response of coho salmon populations to wetland restoration are limited. I investigated two cohorts of juvenile coho salmon growth, movement, and survival within the Humboldt Bay drainage in California. My study sites included restoration features and other sample areas in upland creek habitat and in lowland estuarine wetlands that were located in the four largest watersheds within the Humboldt Bay drainage. The objectives of this study were to: (1) determine if coho salmon are using restored, …


Comparing Fish Species Assemblage Between Impacted And Restored Estuarine Salt Marshes Within The Eel River Estuary, Humboldt Co. Ca, Adam Aguilar, Isaac Basham-Clair, Tristan F. Parkinson, Larkin C. Wells Jan 2023

Comparing Fish Species Assemblage Between Impacted And Restored Estuarine Salt Marshes Within The Eel River Estuary, Humboldt Co. Ca, Adam Aguilar, Isaac Basham-Clair, Tristan F. Parkinson, Larkin C. Wells

Cal Poly Humboldt Capstone Honor Roll

This report details a study assessing the fish assemblages of a recently restored estuarine salt marsh site, and a similar unrestored and impacted site along the Eel River estuary. These two sites are located within the Eel River (Wiya’t) estuary, roughly 10 miles west of the city of Fortuna, CA. This study was conducted during the months of September through October 2023. Data collection was done through seine net dragging at randomly selected sample points across both sites. Seine net hauls were recorded by species and species count, which were later computed using a diversity index to provide values representative …


Analysis Of Ecological Tradeoffs Between Congeneric Shrimp In Coastal Mississippi Waters, Baylor K. Lynch Dec 2022

Analysis Of Ecological Tradeoffs Between Congeneric Shrimp In Coastal Mississippi Waters, Baylor K. Lynch

Honors Theses

Palaemonidae is an ecologically important and abundant family of shrimp that link the benthos to many estuarine food webs. Palaemon pugio and Palaemon vulgaris regularly co-occur along estuarine edge habitats despite previous studies suggesting different preferred sediment types and salinity regimes. The objective was to determine if competition is occurring between the congeners by comparing their relative abundance and assessing isotope niche space along an estuarine gradient. I seasonally sampled various edge habitats at four sites throughout Biloxi Bay, MS, using fyke nets fished over a tidal cycle from November 2020 to November 2021. Collected organisms were identified to the …


Heavy Metal Distribution Across Three Georgia Estuaries Using Coastal Sharks As Sentinel Species, Allyson Stiles Aug 2022

Heavy Metal Distribution Across Three Georgia Estuaries Using Coastal Sharks As Sentinel Species, Allyson Stiles

Master of Science in Integrative Biology Theses

Estuaries are transitional environments that play key roles in coastal ecosystem functioning by providing essential habitats to ecologically important plant and animal species. Estuaries are exposed to a number of anthropogenic impacts, including heavy metal contamination from human activities. However, few studies have examined heavy metal distribution within Georgia’s estuaries and how intact salt marsh ecosystems could play a role in filtering and sequestering contaminants, such as Mercury (Hg). This thesis examined blood total mercury (THg) concentrations of four coastal shark species and concentrations of five heavy metals (Hg, As, Cr, Cu, and Pb) within the water and sediments of …


Effects Of Shoreline Development And Freshwater Discharge On Nekton Assemblage And Trophic Structure In A Northern Gulf Of Mexico Estuary, Glenn Schumacher Aug 2022

Effects Of Shoreline Development And Freshwater Discharge On Nekton Assemblage And Trophic Structure In A Northern Gulf Of Mexico Estuary, Glenn Schumacher

Master's Theses

Coastal salt marshes support a diversity of nekton and facilitate critical ecosystem functions but are threatened by shoreline development and climate change. Therefore, coastal ecosystem managers have begun incentivizing the use of living shorelines (LS), erosion control structures incorporating native plantings, to mitigate ecological consequences of marsh loss. However, post-restoration climate changes may shift habitat templates and negate positive effects of ecosystem restoration. I evaluated the ecology nekton along LS, natural marshes, hardened shorelines and greyed shorelines within Biloxi Bay, Mississippi, during a high freshwater discharge (HFD) period by comparing nekton assemblage (using species richness, Shannon-Wiener diversity, and relative abundance), …


Distribution Patterns Of The Invasive Mussel Arcuatula Senhousia In Mission Bay, San Diego, California: Effects Of Sediment Grain Size And Byssus Thread Production On Predation, Samantha Ahlman May 2022

Distribution Patterns Of The Invasive Mussel Arcuatula Senhousia In Mission Bay, San Diego, California: Effects Of Sediment Grain Size And Byssus Thread Production On Predation, Samantha Ahlman

Theses

The ability of bivalves to avoid predation by using defensive behaviors such as burrowing and byssus production may vary depending on the sediment characteristics of a given habitat. The varying sediment characteristics that change with water velocity within estuaries may influence the distribution of bivalves and limit them to areas that optimize their ability to defend against predators. We examined the distribution patterns of the invasive Asian date mussel Arcuatula senhousia relative to the sediment grain size distribution in Mission Bay, an urban estuary located in San Diego, California, USA. Mussels and sediment were collected using an Ekman grab at …


The Effects Of Short-Term Sea Level Rise On Vegetation Communities In Coastal Mississippi, Brianna Michelle Andrews May 2022

The Effects Of Short-Term Sea Level Rise On Vegetation Communities In Coastal Mississippi, Brianna Michelle Andrews

Theses and Dissertations

Salt marshes are important habitats that provide many ecosystem services, but they are susceptible to the impacts of sea level rise (SLR), often resulting in emergent vegetation loss. In areas with enough sediment input, marshes can keep pace with SLR by gaining elevation or through upland migration. However, salt marshes in areas with limited sediment input, such as the Grand Bay National Estuarine Research Reserve, often cannot keep pace with sea level rise. Additionally, the rate of SLR is increasing making it more difficult for marshes to keep pace. To assess the short-term response of marsh vegetation to sea level …


Effects Of Salinity On Eastern Oysters: Locating Lower-Salinity Tolerant Populations And Defining Resource Zones Suitable To Restoration, Fisheries, And Aquaculture., Lauren Swam Jul 2021

Effects Of Salinity On Eastern Oysters: Locating Lower-Salinity Tolerant Populations And Defining Resource Zones Suitable To Restoration, Fisheries, And Aquaculture., Lauren Swam

LSU Master's Theses

Eastern oysters (Crassostrea virginica) provide valuable ecosystem services and support a productive commercial industry in the northern Gulf of Mexico. Declining abundance from water quality changes and other factors drives development of management and restoration strategies focused on a comprehensive, metapopulation approach. Identifying oyster resource zones based on water quality combined with selective breeding of oysters adapted to specific conditions provides strategies to support aquaculture development and ensure resilient oyster populations and high production. Using 2015-2019 satellite-derived continuous salinity and temperature data for coastal Louisiana, this work created maps defining oyster resource zones supportive of (1) broodstock sanctuary …


Molecular Detection Of Pathogenic Leptospira And Microbial Source Tracking Of Fecal Pollution In San Juan, Puerto Rico, Taylor I. Chapman May 2021

Molecular Detection Of Pathogenic Leptospira And Microbial Source Tracking Of Fecal Pollution In San Juan, Puerto Rico, Taylor I. Chapman

Biology Theses

Leptospirosis, caused by pathogenic Leptospira, is endemic to tropical regions. Leptospira is released into the environment through the secretion of urine from animals, making it easily transmissible through water sources. The estuarian environment surrounding the area of San Juan, Puerto Rico and its high density of urban development creates ideal conditions for transmission of Leptospirosis. The goal of this study was to determine the presence of Leptospira in these surface waters and use Microbial Source Tracking (MST) to identify the possible source of pathogenic Leptospira. Eighty-seven water samples were collected during the dry (44) and wet (43) seasons. …


Water Clarity At The River-Estuary Transition Zone: A Comparative Study Of The James, Mattaponi, And Pamunkey Sub-Estuaries, Rachel Henderson Jan 2021

Water Clarity At The River-Estuary Transition Zone: A Comparative Study Of The James, Mattaponi, And Pamunkey Sub-Estuaries, Rachel Henderson

Theses and Dissertations

Water clarity is a key parameter for monitoring water quality and often used to assess habitat suitability for submerged aquatic vegetation (SAV). Light attenuation, a measure of water clarity, is impacted by colored dissolved organic matter (CDOM), and by suspended particulates which include living and non-living components. We anticipated that the relative importance of these factors in regulating light attenuation would vary among the upper portions of three sub-estuaries differing in morphometry, hydrology, and degree of human influence. The James is characterized by eutrophic conditions and high algal abundance, whereas the Mattaponi and Pamunkey exhibit lower phytoplankton production. The Mattaponi …


Eelgrass (Zostera Marina) Population Decline In Morro Bay, Ca: A Meta-Analysis Of Herbicide Application In San Luis Obispo County And Morro Bay Watershed, Tyler King Sinnott Dec 2020

Eelgrass (Zostera Marina) Population Decline In Morro Bay, Ca: A Meta-Analysis Of Herbicide Application In San Luis Obispo County And Morro Bay Watershed, Tyler King Sinnott

Master's Theses

The endemic eelgrass (Zostera marina) community of Morro Bay Estuary, located on the central coast of California, has experienced an estimated decline of 95% in occupied area (reduction of 344 acres to 20 acres) from 2008 to 2017 for reasons that are not yet definitively clear. One possible driver of degradation that has yet to be investigated is the role of herbicides from agricultural fields in the watershed that feeds into the estuary. Thus, the primary research goal of this project was to better understand temporal and spatial trends of herbicide use within the context of San Luis …


Influence Of Salinity On Copper-Ligand Formation Constants, Fatimah Barnawi Jan 2020

Influence Of Salinity On Copper-Ligand Formation Constants, Fatimah Barnawi

Theses and Dissertations (Comprehensive)

Natural Organic Matter (NOM) is known to reduce metal, such as copper, toxicity in aquatic environments. Copper is essential for organisms, but elevated concentrations of dissolved copper can potentially be toxic. The toxicity of copper is related to its bioavailability, which is influenced by toxicity modifying factors, such as NOM (quantified as Dissolved Organic Carbon (DOC) in mg C/L), alkalinity, pH and major cation and anion concentrations. The principles are the same for fresh and saltwater, but the influence of high salt concentrations, such as in estuaries, and associated activity corrections, can modify NOM complexation of metals (i.e., modify logK …


Exploring The Effects Of Dam Removals On Zooplankton In Penobscot Estuary, Erin Bucci, Karen Wilson Apr 2019

Exploring The Effects Of Dam Removals On Zooplankton In Penobscot Estuary, Erin Bucci, Karen Wilson

Thinking Matters Symposium Archive

Estuaries provide many ecosystem services such as buffering the negative impacts of storms, offering recreation and commercial fishing opportunities, and they serve as a critical habitat corridor for migratory fish. In New England, estuarine habitats have been dramatically altered over the last 200 years due to dam construction; migratory fish such as Atlantic salmon and alewives have suffered. Recently, there have been several dam removal projects in Maine aimed to restore these populations – the largest of these efforts being the Penobscot River Restoration Project. In 2013, two dams were removed from the Penobscot River Estuary, opening more than 2,000 …


Seaweed Community Structure Along Environmental Gradients In An Ocean-Dominated Estuary, Saskia A. Raether Jan 2019

Seaweed Community Structure Along Environmental Gradients In An Ocean-Dominated Estuary, Saskia A. Raether

Cal Poly Humboldt theses and projects

Macrophyte community structure in estuaries that have been modified by the addition of hard substrata are poorly documented, especially in relation to the physical and environmental gradients that shape them. Therefore, this study describes the summer macrophyte flora that occurs on hard and soft substrata throughout Humboldt Bay, CA and tests how the macrophyte communities correlate to measures of horizontal and vertical environmental gradients. The percent cover of macroalgae, vascular plants, cyanobacteria, lichens, diatom film, sessile invertebrates, and substratum types were quantified during the summers of 2017 and 2018 at eleven intertidal locations in the bay and outer coast. Horizontal …


Environmental Conditions In San Martin Lake: Effects Of Eutrophication In An Estuary Associated With The Laguna Madre, Wendy L. Rogers Aug 2018

Environmental Conditions In San Martin Lake: Effects Of Eutrophication In An Estuary Associated With The Laguna Madre, Wendy L. Rogers

Theses and Dissertations

San Martin Lake is a shallow water Estuary in the lower Laguna Madre off the Port of Brownsville Shipping channel. It is influenced both by incoming tides and waste water runoff both from local farms and the Brownsville water treatment plants. The resulting mixture of eutrophic water and incoming sea water creates the perfect mix for a potential algal bloom. This study looks at the nutrient levels and environmental conditions in the main basin of the estuary to establish baseline levels and to observe the rate of nutrient clearing being accomplished in this environment. As sport recreation in the area …


Assessment And Mapping Of The Milwaukee Estuary Habitat, Brennan Dow May 2018

Assessment And Mapping Of The Milwaukee Estuary Habitat, Brennan Dow

Theses and Dissertations

Rivermouth regions such as the Milwaukee Harbor, are the habitat interface between watersheds and the Great Lakes proper, and can host a large diversity of fishes. To facilitate an ecosystem approach management strategy, I developed a layered map that includes bathymetry, side scan sonar images, shoreline substrate classifications, and initial data of aquatic vegetation and centrarchid spawning locations. The 60 km perimeter of the study area consisted of 59% hardened shoreline. Ground truthing of substrate classifications via Ponar grabs or video had about 95% accuracy for fine and rocky boulder substrates. Rocky fine was the most inaccurate classification (35%), but …


Detrital Protein Contributes To Oyster Nutrition And Growth In The Damariscotta Estuary, Maine, Usa, Cheyenne M. Adams May 2018

Detrital Protein Contributes To Oyster Nutrition And Growth In The Damariscotta Estuary, Maine, Usa, Cheyenne M. Adams

Electronic Theses and Dissertations

Oyster aquaculture is an expanding industry that relies on identifying and utilizing natural estuarine conditions for the economically viable production of a filter-feeding crop. The eastern oyster, Crassostrea virginica, is the principal species currently cultured in Maine. In addition to preferentially consumed phytoplankton, various detrital complexes (non-algal and/or non-living organic matter) may provide some nutrition to C. virginica between times of phytoplankton abundance. Here I investigated the importance of detrital proteins in supporting the growth of oysters cultured in the upper Damariscotta Estuary. Oyster aquaculture in this area is highly successful and previous reports indicate that labile detrital protein …


Tidal Creek And Substrate Effects On Oyster Reef Associated Fish And Decapod Condition And Density, Thomas S. Funk Apr 2018

Tidal Creek And Substrate Effects On Oyster Reef Associated Fish And Decapod Condition And Density, Thomas S. Funk

Electronic Theses and Dissertations

Oyster reefs are essential fish habitat and a worldwide loss of reefs has the potential to negatively affect reef-associated nekton populations. Along the 100 km Myrtle Beach, SC shoreline, oyster reefs ostensibly have disappeared within swash tidal creeks, which are anthropogenically altered estuarine systems that drain into the coastal ocean directly over shoreline beaches. To address oyster reef losses, a series of shell bag reefs were constructed within multiple swash tidal creeks. Reefs also were constructed in tidal creeks associated with estuaries directly connected to the ocean by an inlet. The purpose of this study was to compare nekton usage …


A Comparison Of Computational Methods For Estimating Estuarine Production And Respiration From Diel Open Water Dissolved Oxygen Measurements, Spencer Tassone Jan 2017

A Comparison Of Computational Methods For Estimating Estuarine Production And Respiration From Diel Open Water Dissolved Oxygen Measurements, Spencer Tassone

Theses and Dissertations

Diel dissolved oxygen (DO) data were used to characterize seasonal, inter-annual, and longitudinal variation in production and respiration for the James River Estuary. Two computational methods (Bayesian and bookkeeping) were applied to these data to determine whether inferences regarding DO metabolism are sensitive to methodology. Net metabolism was sensitive to methodology as Bayesian results indicated net heterotrophy (production < respiration) while bookkeeping results indicated net autotrophy (production > respiration). Differences in net metabolism among the methods was due to low seasonal variation in respiration using the Bayesian method, whereas bookkeeping results showed a strong correlation between production and respiration. Bayesian results suggest a dependence on allochthonous organic matter (OM) whereas …


Pollutants And Foraminiferal Assemblages In Torrecillas Lagoon: An Environmental Micropaleontology Approach, Michael Martinez-Colon Jun 2016

Pollutants And Foraminiferal Assemblages In Torrecillas Lagoon: An Environmental Micropaleontology Approach, Michael Martinez-Colon

USF Tampa Graduate Theses and Dissertations

Torrecillas Lagoon in the North Coast of Puerto Rico has experienced extensive anthropogenic influence over the past 400 years. Elevated concentrations of Potential Toxic Elements (PTEs) have been reported in surficial sediments. The main goal of this dissertation was to implement in Puerto Rico the use of benthic foraminifers as a bioindicators of PTEs and to compare the impact of Cu(II) on field samples with results of experimental work using cultures.

Analyses included geochemical assessment for bulk and carbonate- soluble bioavailable concentrations of PTEs in surface, core and pore-water samples, as well as analyses of grain-size, Percent Total Organic Carbon …


Evaluation Of The Estrogenic And Osmoregulatory Impacts Of Exposure To 4-Nonylphenol Pollution In The Estuarine Arrow Goby, Clevelandia Ios, Kaitlin Marie Johnson Jun 2016

Evaluation Of The Estrogenic And Osmoregulatory Impacts Of Exposure To 4-Nonylphenol Pollution In The Estuarine Arrow Goby, Clevelandia Ios, Kaitlin Marie Johnson

Master's Theses

Recent evidence indicates that some of California’s coastal estuaries are contaminated with the chemical 4-nonylphenol (4-NP). Tissue burdens of 4-NP detected in the intertidal arrow goby (Clevelandia ios) in California are among the highest recorded worldwide, however, it remains unknown whether these fish are impacted by this 4-NP contamination. 4-NP is an established endocrine disrupting compound with estrogenic properties that can alter reproductive function. Furthermore, evidence that estrogens can modulate iono- and osmo-regulatory function in fishes implies that estuarine fishes exposed to 4-NP may also experience an impaired ability to maintain hydromineral balance. In Chapter 1 of this …


Bioavailability Of Dissolved Organic Matter In The North Inlet Estuary, Andrew Mason Gaines Banks May 2016

Bioavailability Of Dissolved Organic Matter In The North Inlet Estuary, Andrew Mason Gaines Banks

Senior Theses

Dissolved organic matter (DOM) is an important source of carbon and energy for microbial food webs in estuaries. The export of DOM from estuaries to the coastal ocean influences shelf productivity and biogeochemical cycles. Chromophoric dissolved organic matter (CDOM) is an important component of the DOM pool that absorbs light, and is photoreactive. There are various optical properties of CDOM that can be used to indicate the sources of DOM, such as whether or not it is derived from terrestrial or marine environments. In this study, the sources and bioavailability of DOM were characterized in the North Inlet estuary near …


Management Recommendations For Restoration Of The Degraded Olympia Oyster, Ostrea Lurida Carpenter 1864 In Tomales Bay, Ca, Carolyn M. Gibson May 2015

Management Recommendations For Restoration Of The Degraded Olympia Oyster, Ostrea Lurida Carpenter 1864 In Tomales Bay, Ca, Carolyn M. Gibson

Master's Projects and Capstones

This research addresses the effective restoration of Olympia oyster populations in Tomales Bay, Marin County, California. Chapter 2 provides background information on the Tomales Bay estuary, regional history, and ecology of the Olympia oyster. Following this background discussion, each of the three aforementioned degraders of Olympia oyster populations in Tomales Bay is presented: ocean acidification (Chapter 3), sedimentation (Chapter 4), and invasive species (Chapter 5). Each of these issues creates numerous barriers that require the attention of resource protection managers. Chapter 6 presents overall Research Conclusions and Chapter 7 identifies management recommendations to effectively begin the restoration of the Olympia …


Identifying Inundation-Driven Effects Among Intertidal Crassostrea Virginica In A Commercially Important Gulf Of Mexico Estuary, Joshua Solomon Jan 2015

Identifying Inundation-Driven Effects Among Intertidal Crassostrea Virginica In A Commercially Important Gulf Of Mexico Estuary, Joshua Solomon

Electronic Theses and Dissertations

Sea level rise and changing storm frequency and intensity resulting from climate change create tremendous amounts of uncertainty for coastal species. Intertidal species may be especially affected since they are dependent on daily inundation and exposure. The eastern oyster Crassostrea virginica is an economically and biologically important sessile intertidal species ranging from Canada to the Gulf of Mexico. Declines and changes in distribution of oyster populations has forced commercial harvesting to spread from subtidal to intertidal reefs. We investigated the potential responses of intertidal C. virginica to sea level rise, and the response of larval settlement to sedimentation which is …


Carbon Storage And Preservation In Seagrass Meadows, Mohammad Rozaimi Jamaludin Jan 2015

Carbon Storage And Preservation In Seagrass Meadows, Mohammad Rozaimi Jamaludin

Theses: Doctorates and Masters

Seagrass meadows are important ‘Blue Carbon’ sinks but many questions remain unaddressed in regards to the organic carbon (OC) sequestration capacity and processes leading to retention and persistence of OC in seagrass sediments. The research summarised in this dissertation examined 37 sediment cores from twelve Australian seagrass meadows (Posidonia australis and Halophila ovalis) in order to improve our understanding of OC storage and preservation in seagrass sediments. The research: quantified the OC storage in seagrass meadows and the reduction in stores after ecosystem degradation; the rates of OC accumulation; the roles of species composition and the depositional nature …


Effects Of The Algal Toxin Microcystin On Fishes In The James River, Virginia, Maxwell D. Haase Jan 2015

Effects Of The Algal Toxin Microcystin On Fishes In The James River, Virginia, Maxwell D. Haase

Theses and Dissertations

With the global rise in frequency of harmful algal blooms in estuarine environments comes an increase in prevalence of toxic metabolites, such as microcystin (MC), that some of the cyanobacteria involved will produce. At high concentrations, MC may accumulate in consumer tissues and have deleterious effects on organisms; however impacts of the toxin on aquatic living resources at ecologically relevant concentrations have not been widely documented. We analyzed the effects of MC on juveniles of five fish species from the James River, Virginia to determine if MC has the potential to impede growth. Using three separate experimental approaches, it was …


Denitrification In Urban Coastal Environments: A Functional Gene Study, Samantha Denise Lindemann Jan 2014

Denitrification In Urban Coastal Environments: A Functional Gene Study, Samantha Denise Lindemann

Master's Theses

Eutrophication is a major anthropogenic stressor on aquatic ecosystems worldwide. Jamaica Bay is located in the southeastern portion of New York City, NY (NYC). Like many other estuaries, Jamaica Bay is impacted by anthropogenic N inputs from various sources. Despite eutrophic conditions, improvements in water quality over the last few decades have prompted government agencies to promote oyster restoration to help reduce anthropogenic N in NYC waters. The effect of eastern oysters on sediment bacterial communities responsible for denitrification in Jamaica Bay was previously unknown. Those samples exposed to oysters were predicted to have high denitrification gene abundances, and thus …