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Water quality

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Full-Text Articles in Physical Sciences and Mathematics

A Data Repository For Clarifying Water Clarity: A Call To Use Metrics Best Suited To Corresponding Research And Management Goals In Aquatic Ecosystems (York River Estuary Case Study Dataset), Jessica S. Turner, Kelsey A. Fall, Carl T. Friedrichs Jan 2022

A Data Repository For Clarifying Water Clarity: A Call To Use Metrics Best Suited To Corresponding Research And Management Goals In Aquatic Ecosystems (York River Estuary Case Study Dataset), Jessica S. Turner, Kelsey A. Fall, Carl T. Friedrichs

Data

This data repository is a permanent archive of the results presented in the associated publication (Turner et al. 2022, Limnology & Oceanography Letters, doi.xxxx). The objective of this study was to illustrate a water clarity phenomenon in the lower York River Estuary of the Chesapeake Bay. The data include light attenuation, Secchi depth, turbidity, and salinity from the lower York River Estuary in western Chesapeake Bay, Virginia, USA from the years 2014-2016.


Wild Pig Removal Reduces Pathogenic Bacteria In Low-Order Streams, Sara A. Bolds, B. Graeme Lockaby, Latif Kalin, Stephen S. Ditchkoff, Mark D. Smith, Kurt Vercauteren Jan 2022

Wild Pig Removal Reduces Pathogenic Bacteria In Low-Order Streams, Sara A. Bolds, B. Graeme Lockaby, Latif Kalin, Stephen S. Ditchkoff, Mark D. Smith, Kurt Vercauteren

USDA Wildlife Services: Staff Publications

Invasive wild pig populations have undergone enormous increases in the United States and particularly across the southern U.S. in recent years. High fecundity rates and abilities to adapt quickly to varied habitats have enabled pig populations to become entrenched and difficult to eliminate. The pigs cause many negative impacts on ecosystems including degradation of water quality through infusion of fecal contamination and other non-point source pollutants. Our goal was to determine the effects of pig removal on water quality in streams that were known to be significantly polluted by pig activity Bolds (J Environ Qual 50: 441–453, 2021). We compared …


Dammed Water Quality—Longitudinal Stream Responses Below Beaver Ponds In The Umpqua River Basin, Oregon, John R. Stevenson, Jason B. Dunham, Steven M. Wondzell, Jimmy Taylor Jan 2022

Dammed Water Quality—Longitudinal Stream Responses Below Beaver Ponds In The Umpqua River Basin, Oregon, John R. Stevenson, Jason B. Dunham, Steven M. Wondzell, Jimmy Taylor

USDA Wildlife Services: Staff Publications

Beaver-related restoration (BRR) has gained popularity as a means of improving stream ecosystems, but the effects are not fully understood. Studies of dissolved oxygen (DO) and water temperature, key water quality metrics for salmonids, have demonstrated improved conditions in some cases, but warming and decreased DO have been more commonly reported in meta-analyses. These results point to the contingencies that can influence outcomes from BRR. We examined water quality related to beaver ponds in a diverse coastal watershed (Umpqua River Basin, OR, USA). We monitored water temperature 0–400m above and below beaver ponds and at pond surfaces and bottoms across …


Simulated Response Of St. Joseph Bay, Florida, Seagrass Meadows And Their Belowground Carbon To Anthropogenic And Climate Impacts, Marie Cindy Lebrasse, Blake A. Schaeffer, Richard C. Zimmerman, Victoria J. Hill, Megan M. Coffer, Peter J. Whitman, Wilson B. Salls, David D. Graybill, Christopher L. Osburn Jan 2022

Simulated Response Of St. Joseph Bay, Florida, Seagrass Meadows And Their Belowground Carbon To Anthropogenic And Climate Impacts, Marie Cindy Lebrasse, Blake A. Schaeffer, Richard C. Zimmerman, Victoria J. Hill, Megan M. Coffer, Peter J. Whitman, Wilson B. Salls, David D. Graybill, Christopher L. Osburn

OES Faculty Publications

Seagrass meadows are degraded globally and continue to decline in areal extent due to human pressures and climate change. This study used the bio-optical model GrassLight to explore the impact of climate change and anthropogenic stressors on seagrass extent, leaf area index (LAI) and belowground organic carbon (BGC) in St. Joseph Bay, Florida, using water quality data and remotely-sensed sea surface temperature (SST) from 2002 to 2020. Model predictions were compared with satellite-derived measurements of seagrass extent and shoot density from the Landsat images for the same period. The GrassLight-derived area of potential seagrass habitat ranged from 36.2 km2 …


Great South Bay, Long Island, New York Summer Water Quality Monitoring Program, Cercom, Molloy University, John Tanacredi Ph.D., Kyle F. Maurelli Jan 2022

Great South Bay, Long Island, New York Summer Water Quality Monitoring Program, Cercom, Molloy University, John Tanacredi Ph.D., Kyle F. Maurelli

CERCOM Reports

The Center for Environmental Research and Coastal Oceans Monitoring (CERCOM) visits 11 locations in the Great South Bay from Memorial Day – Labor Day to monitor dissolved oxygen (DO), pH, salinity, clarity and temperature. Students are trained to assist in CERCOM’s water quality data collection by research assistant Mr. Kyle Maurelli. This monitoring program has been conducted for the past 17 years. These parameters are critical in determining long term water quality conditions in Long Island estuaries


Nutrient Improvements In Chesapeake Bay: Direct Effect Of Load Reductions And Implications For Coastal Management, Rebecca R. Murphy, Jennifer Keisman, Jon Harcum, Renee R. Karrh, Mike Lane, Elgin S. Perry, Qian Zhang Jan 2022

Nutrient Improvements In Chesapeake Bay: Direct Effect Of Load Reductions And Implications For Coastal Management, Rebecca R. Murphy, Jennifer Keisman, Jon Harcum, Renee R. Karrh, Mike Lane, Elgin S. Perry, Qian Zhang

Biological Sciences Faculty Publications

In Chesapeake Bay in the United States, decades of management efforts have resulted in modest reductions of nutrient loads from the watershed, but the corresponding improvements in estuarine water quality have not consistently followed. Generalized additive models were used to directly link river flows and nutrient loads from the watershed to nutrient trends in the estuary on a station-by-station basis, which allowed for identification of exactly when and where responses are happening. Results show that Chesapeake Bay’s total nitrogen and total phosphorus conditions are mostly improving after accounting for variation in freshwater flow. Almost all of these improving nutrient concentrations …


A Biological And Chemical Approach To Restoring Water Quality: A Case Study In An Urban Eutrophic Pond, Levi J. Mckercher, Tiffany L. Messer, Aaron R. Mittelstet, Steve D. Comfort Jan 2022

A Biological And Chemical Approach To Restoring Water Quality: A Case Study In An Urban Eutrophic Pond, Levi J. Mckercher, Tiffany L. Messer, Aaron R. Mittelstet, Steve D. Comfort

School of Natural Resources: Faculty Publications

Efforts to improve water quality of eutrophic ponds often involve implementing changes to watershed management practices to reduce external nutrient loads. While this is required for long-term recovery and prevention, eutrophic conditions are often sustained through the recycling of internal nutrients already present within the waterbody. In particular, internal phosphorus bound to organic material and adsorbed to sediment has the potential to delay lake recovery for decades. Thus, pond and watershed management techniques are needed that not only reduce external nutrient loading but also mitigate the effects of internal nutrients already present. Therefore, our objective was to demonstrate a biological …


Feasibility Of Development Of Flood Resiliency Clearinghouse Program, Commonwealth Center For Recurrent Flooding Resiliency, Mujde Erten-Unal, Carol Considine, Mark W. Luckenbach, Elizabeth Armistead Andrews Nov 2021

Feasibility Of Development Of Flood Resiliency Clearinghouse Program, Commonwealth Center For Recurrent Flooding Resiliency, Mujde Erten-Unal, Carol Considine, Mark W. Luckenbach, Elizabeth Armistead Andrews

Commonwealth Center for Recurrent Flooding Resiliency (CCRFR): Reports

[Introduction]

House Bill 2187i, introduced by Delegate Keith Hodges in the 2021 session of the Virginia General Assembly, directed the Commonwealth Center for Recurrent Flooding Resiliency (CCRFR), a partnership between Old Dominion University, the Virginia Institute of Marine Science (VIMS) and the William & Mary Law School’s Virginia Coastal Policy Center (VCPC) established by Virginia Chapter 440 of the 2016 Acts of Assembly (HB 903), to evaluate the development of a Flood Resiliency Clearinghouse Program (henceforth Clearinghouse). The bill stipulated that the Center should work with the Department of Conservation and Recreation (DCR) to evaluate solutions that manage …


A Biological Assessment Of Water Quality In El Placer, Ecuador: The Effect Of Agriculture On Stream Health And The Quality Of Historical Versus Current Drinking Water Sources, Danielle Kleinberg Oct 2021

A Biological Assessment Of Water Quality In El Placer, Ecuador: The Effect Of Agriculture On Stream Health And The Quality Of Historical Versus Current Drinking Water Sources, Danielle Kleinberg

Independent Study Project (ISP) Collection

Although fresh water is one of Ecuador’s most abundant resources, high quality drinking water for its inhabitants is scarce (Wingfield et al., 2021). The most prevalent sources of water pollution in Ecuador are domestic waste, silver and gold mining, oil production, and agricultural chemicals (Buckalew et al., 1997). El Placer, a village located in Tungurahua, Ecuador, is highly dependent on agriculture as a source of income. The first objective of this study was to determine the effect of agriculture on the El Placer’s Tía Anita Stream through comparing the water quality at three sites with varying agricultural influence. The second …


Chamoli Disaster: Pronounced Changes In Water Quality And Flood Plains Using Sentinel Data, Sansar Raj Meena, Akshansa Chauhan, Kushanav Bhuyan, Ramesh P. Singh Aug 2021

Chamoli Disaster: Pronounced Changes In Water Quality And Flood Plains Using Sentinel Data, Sansar Raj Meena, Akshansa Chauhan, Kushanav Bhuyan, Ramesh P. Singh

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The Himalayan rivers are vulnerable to devastating flooding caused by landslides and outbreak of glacial lakes. On 7 February 2021, a deadly disaster occurred near the Rishi Ganga Hydropower Plant in the Rishi Ganga River, killing more than 100 people. During the event, a large volume of debris and broken glacial fragments flooded the Rishi Ganga River and washed away the Rishi Ganga Hydropower plant ongoing project. This study presents the impact of the Chamoli disaster on the water quality of Rishi Ganga River in upstream near Tapovan and Ganga River in downstream near Haridwar through remote sensing data. Five …


Effects Of Tidal Flooding On Estuarine Biogeochemistry: Quantifying Flood-Driven Nitrogen Inputs In An Urban, Lower Chesapeake Bay Sub-Tributary, Alfonso Macías-Tapia, Margaret R. Mulholland, Corday R. Selden, Jon Derek Loftis, Peter W. Bernhardt Aug 2021

Effects Of Tidal Flooding On Estuarine Biogeochemistry: Quantifying Flood-Driven Nitrogen Inputs In An Urban, Lower Chesapeake Bay Sub-Tributary, Alfonso Macías-Tapia, Margaret R. Mulholland, Corday R. Selden, Jon Derek Loftis, Peter W. Bernhardt

VIMS Articles

Sea level rise has increased the frequency of tidal flooding even without accompanying precipitation in many coastal areas worldwide. As the tide rises, inundates the landscape, and then recedes, it can transport organic and inorganic matter between terrestrial systems and adjacent aquatic environments. However, the chemical and biological effects of tidal flooding on urban estuarine systems remain poorly constrained. Here, we provide the first extensive quantification of floodwater nutrient concentrations during a tidal flooding event and estimate the nitrogen (N) loading to the Lafayette River, an urban tidal sub-tributary of the lower Chesapeake Bay (USA). To enable the scale of …


Butte Treatment Lagoons Daily Pts Field Dump, Pioneer Technical Services, Inc. Jul 2021

Butte Treatment Lagoons Daily Pts Field Dump, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Butte Treatment Lagoon System, Pioneer Technical Services, Inc. Jul 2021

Butte Treatment Lagoon System, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Butte Treatment Lagoon System, Pioneer Technical Services, Inc. Jul 2021

Butte Treatment Lagoon System, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Silver Bow Creek/Butte Area Npl Site Butte Priority Soils Operable Unit, Pioneer Technical Services, Inc. Jul 2021

Silver Bow Creek/Butte Area Npl Site Butte Priority Soils Operable Unit, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Development Of A Python Library To Facilitate Wqx Dataset Exchanges, Jonathan Musselwhite, Fernando Rojano May 2021

Development Of A Python Library To Facilitate Wqx Dataset Exchanges, Jonathan Musselwhite, Fernando Rojano

Presentations

The assistance of programming tools to speed up the exchange of water quality datasets are necessary. These tools reduce and simplify the steps currently needed to transfer datasets from water quality monitoring stations to public databases. Here it is presented a library developed in Python that programmatically covers the steps related to the upload of datasets following the framework of the Water Quality Exchange (WQX) of the US EPA. This library is mainly characterized by its ability to efficiently connect and transfer data formatted as CSV or XLSX files via the WQX to the National STORET Data Warehouse by mostly …


Evaluating Impacts Of Anthropogenic Disturbance To Wetland Water Quality Functions, Sindupa De Silva, Jim Anderson, Jason A. Hubbart, Michael P. Strager, Elliott Kellner, Christopher T. Rota, Elizabeth A. Byers May 2021

Evaluating Impacts Of Anthropogenic Disturbance To Wetland Water Quality Functions, Sindupa De Silva, Jim Anderson, Jason A. Hubbart, Michael P. Strager, Elliott Kellner, Christopher T. Rota, Elizabeth A. Byers

Presentations

Wetland ecosystems play fundamental roles in regulating our freshwater resources, yet they are not comprehensively protected from degradation and loss. West Virginia, USA has wetlands across diverse landscapes and geography that feed into both the Chesapeake Bay and Gulf of Mexico. The state is also comprised of diverse anthropogenic land-use practices. We are assessing 200 wetlands over 2 years to evaluate how anthropogenic disturbance impact wetland water quality functions. Select water quality parameters (20), and relative diversity and abundance of vegetation and macroinvertebrates will be used as bioindicators. They will be compared with GIS assessments of watershed land cover/ land-use …


Coastal Natural And Nature-Based Features (Nnbfs) Ranked: Co-Benefits For Coastal Buildings And Target Areas For The Creation Of New Or Restoration Of Nnbfs In Coastal Virginia, Pamela Mason, Jessica Hendricks, Julie Herman May 2021

Coastal Natural And Nature-Based Features (Nnbfs) Ranked: Co-Benefits For Coastal Buildings And Target Areas For The Creation Of New Or Restoration Of Nnbfs In Coastal Virginia, Pamela Mason, Jessica Hendricks, Julie Herman

Data

Community resilience to storm-driven coastal flooding is improved with the presence of natural and nature-based features (NNBFs) such as wetlands, wooded areas, living shorelines, and beaches. These natural and created features can provide multiple benefits for a local community, including mitigating the impacts of storm surge and sea-level rise and allowing communities to take advantage of programmatic incentive programs like FEMA’s Community Rating System and nutrient reduction crediting.

As part of a NOAA-funded project NA17NOS4730142, an exportable geospatial protocol and NNBF ranking methodology was developed with the goal of incentivizing the protection and creation of NNBFs across Chesapeake Bay localities …


Water Quality In Accomack County Freshwater Streams 2020, Richard A. Snyder, Paige G. Ross Feb 2021

Water Quality In Accomack County Freshwater Streams 2020, Richard A. Snyder, Paige G. Ross

Reports

Expansion of poultry house operations and use of litter as a soil amendment in Accomack County Virginia has raised concerns for water quality impacts on both seaside and bayside of the Eastern Shore of Virginia (ESVA). This ongoing investigation is examining freshwater stream water quality in Accomack Virginia to identify water quality impairments from poultry operation storm water runoff. Previous sampling data from 2019 has been integrated into this report. Sampling in 2020 followed an extended drought period (base flow) and two inch rainfall events (storm flow) in streams at road crossings in Accomack County Bayside and Seaside drainages. Dissolved …


Surface Water Nitrogen Attenuation From The Accomack County, Va Southern Landfill Groundwater Discharge - Final Report, Richard A. Snyder, Paige G. Ross Feb 2021

Surface Water Nitrogen Attenuation From The Accomack County, Va Southern Landfill Groundwater Discharge - Final Report, Richard A. Snyder, Paige G. Ross

Reports

Previous sampling of the stream crossing Bobtown Road (Rt 178) near the intersection of Hollies Church Road (Rt. 620), had indicated high levels of nitrogen in the stream flow (Snyder and Ross, 2019a). The proximity of the retired Accomack County Landfill upstream of the site triggered a higher resolution sampling of the stream in an attempt to isolate a source of the nitrogen loading (Snyder and Ross, 2019b). Accomack County has requested repeated sampling of this stream segment to monitor nutrient attenuation trends from the site, and stations were established for that purpose. This Final Report provides a summary of …


Best Management Practices For Firefighting In The Karstic Edwards (Balcones Fault Zone) Aquifer Of South-Central Texas, Geary M. Schindel, Rudolph A. Rosen Jan 2021

Best Management Practices For Firefighting In The Karstic Edwards (Balcones Fault Zone) Aquifer Of South-Central Texas, Geary M. Schindel, Rudolph A. Rosen

Water Resources Science and Technology Faculty Publications

Karst aquifers are vulnerable to contamination from hazardous pollutants that can harm drinking water supplies, species inhabiting aquifers and springs, and other karst water resources. This paper presents best management practices (BMPs) designed for use by first responders, and for use in developing training curricula and tools to assist first responders in protecting karst water resources. Training and tools based on the BMPs will help first responders prevent or reduce runoff of potentially hazardous materials that can rapidly enter an aquifer during firefighting and other responses to emergencies in locations where hazardous materials are stored, such as in retail centers, …


Impacts Of Multiple Environmental Changes On Long‐Term Nitrogen Loading From The Chesapeake Bay Watershed, Shufen Pan, Zihao Bian, Hanqin Tian, Yuanzhi Yao, Raymond G. Najjar, Marjorie A.M. Friedrichs, Eileen E. Hofmann, Rongting Xu, Bowen Zhang Jan 2021

Impacts Of Multiple Environmental Changes On Long‐Term Nitrogen Loading From The Chesapeake Bay Watershed, Shufen Pan, Zihao Bian, Hanqin Tian, Yuanzhi Yao, Raymond G. Najjar, Marjorie A.M. Friedrichs, Eileen E. Hofmann, Rongting Xu, Bowen Zhang

CCPO Publications

Excessive nutrient inputs from land, particularly nitrogen (N), have been found to increase the occurrence of hypoxia and harmful algal blooms in coastal ecosystems. To identify the main contributors of increased N loading and evaluate the efficacy of water pollution control policies, it is essential to quantify and attribute the long‐term changes in riverine N export. Here, we use a state‐of‐the‐art terrestrial–aquatic interface model to examine how multiple environmental factors may have affected N export from the Chesapeake Bay watershed since 1900. These factors include changes in climate, carbon dioxide, land use, and N inputs (i.e., atmospheric N deposition, animal …


Water Quality Monitoring In The Upper Poteau River Watershed, Abbie Lasater, Brian E. Haggard Jan 2021

Water Quality Monitoring In The Upper Poteau River Watershed, Abbie Lasater, Brian E. Haggard

Technical Reports

The Upper Poteau River Watershed (UPRW) has been listed as a priority watershed in Arkansas since 1998 due to nutrient and sediment enrichment from point and nonpoint sources (NPS). According to the Arkansas NPS pollution management plan, the goals for the UPRW are to reduce pollutant levels that will restore all designates uses and target subwatersheds where implementation of management practices can have the greatest impact. Over the last several years, many 319(h) projects have been implemented and point sources have been reduced in order to improve water quality in the UPRW. The purpose of this study was to monitor …


A Data Repository For Extent And Causes Of Chesapeake Bay Warming, Kyle E. Hinson, Marjorie A.M. Friedrichs, Pierre St-Laurent Jan 2021

A Data Repository For Extent And Causes Of Chesapeake Bay Warming, Kyle E. Hinson, Marjorie A.M. Friedrichs, Pierre St-Laurent

Data

This data repository is a permanent archive of the results presented in the associated publication (Hinson et al. 2021, Journal of the American Water Resources Association, 1–21. https://doi.org/10.1111/1752-1688.12916


A Data Repository For Effects Of Reduced Shoreline Erosion On Chesapeake Bay Water Clarity, Jessica Turner, Pierre St-Laurent, Marjorie A.M. Friedrichs, Carl T. Friedrichs Jan 2021

A Data Repository For Effects Of Reduced Shoreline Erosion On Chesapeake Bay Water Clarity, Jessica Turner, Pierre St-Laurent, Marjorie A.M. Friedrichs, Carl T. Friedrichs

Data

This data repository is a permanent archive of the results presented in the associated publication (Turner et al. 2020, Science of the Total Environment, doi: 10.1016/j.scitotenv.2021.145157).

The objective of this study was to investigate the effects of shoreline erosion on water clarity in the Chesapeake Bay. To this end, we used the Chesapeake Bay ROMS Estuarine Carbon and Biogeochemistry (ChesROMS-ECB), a biogeochemical model embedded in the Regional Ocean Modeling System (ROMS). Using this model, we simulated a Chesapeake Bay estuary from 2001-2005 with varying magnitudes of sediment inputs from shoreline erosion and varying seabed erodibility conditions. Model results were compared …


Effects Of Tidal Flooding On Estuarine Biogeochemistry: Quantifying Flood-Driven Nitrogen Inputs In An Urban, Lower Chesapeake Bay Sub-Tributary, Alfonso Macías-Tapia, Margaret R. Mulholland, Corday R. Selden, J. Derek Loftis, Peter W. Bernhardt Jan 2021

Effects Of Tidal Flooding On Estuarine Biogeochemistry: Quantifying Flood-Driven Nitrogen Inputs In An Urban, Lower Chesapeake Bay Sub-Tributary, Alfonso Macías-Tapia, Margaret R. Mulholland, Corday R. Selden, J. Derek Loftis, Peter W. Bernhardt

OES Faculty Publications

Sea level rise has increased the frequency of tidal flooding even without accompanying precipitation in many coastal areas worldwide. As the tide rises, inundates the landscape, and then recedes, it can transport organic and inorganic matter between terrestrial systems and adjacent aquatic environments. However, the chemical and biological effects of tidal flooding on urban estuarine systems remain poorly constrained. Here, we provide the first extensive quantification of floodwater nutrient concentrations during a tidal flooding event and estimate the nitrogen (N) loading to the Lafayette River, an urban tidal sub-tributary of the lower Chesapeake Bay (USA). To enable the scale of …


Trends In Water Quality Of Cave Pools At Timpanogos Cave National Monument, July 2008–September 2018, Rebecca Weissinger, Andy Armstrong, Kirsten Bahr, Chris Groves Oct 2020

Trends In Water Quality Of Cave Pools At Timpanogos Cave National Monument, July 2008–September 2018, Rebecca Weissinger, Andy Armstrong, Kirsten Bahr, Chris Groves

Crawford Hydrology Laboratory

No abstract provided.


Occupancy And Abundance Of Stream Salamanders Along A Specific Conductance Gradient, Jacob M. Hutton, Steven J. Price, Simon J. Bonner, Stephen C. Richter, Christopher D. Barton Sep 2020

Occupancy And Abundance Of Stream Salamanders Along A Specific Conductance Gradient, Jacob M. Hutton, Steven J. Price, Simon J. Bonner, Stephen C. Richter, Christopher D. Barton

Forestry and Natural Resources Faculty Publications

In the Central Appalachians (USA), mountaintop-removal mining accompanied by valley fills often leads to streams with elevated specific conductivity (SC). Thus, the ionic composition of freshwaters in this region is hypothesized to be a driver of the distribution and abundance of freshwater taxa, including stream salamanders. We examined the association between SC and stream salamander populations by conducting salamander counts in 30 southeastern Kentucky streams across a continuous gradient of SC that ranged from 30 to 1966 μS/cm. We counted 2319 salamanders across 5 species and, using a hierarchical Bayesian version of the N-mixture model, found a negative association between …


2020 Chesapeake Bay Dead Zone Report, Virginia Institute Of Marine Science, Anchor Qea Sep 2020

2020 Chesapeake Bay Dead Zone Report, Virginia Institute Of Marine Science, Anchor Qea

Reports

The “Dead Zone” of the Chesapeake Bay refers to a volume of bottom water that is characterized by dissolved oxygen concentrations less than 2 mg/L, which is too low for aquatic organisms such as fish and blue crabs to thrive.The Chesapeake Bay experiences such “hypoxic”conditions every year, with the severity varying from year to year, depending on nutrient and freshwater inputs, wind, and temperature. Multiple metrics are used to relate the severity of hypoxia between different years:

  • Hypoxic Duration (days): The number of days in a given year between the first and last day of hypoxic conditions exceeding 2 km3in …


A Machine‐Learning‐Based Model For Water Quality In Coastal Waters, Taking Dissolved Oxygen And Hypoxia In Chesapeake Bay As An Example, Xin Yu, Jian Shen, Jiabi Du Aug 2020

A Machine‐Learning‐Based Model For Water Quality In Coastal Waters, Taking Dissolved Oxygen And Hypoxia In Chesapeake Bay As An Example, Xin Yu, Jian Shen, Jiabi Du

VIMS Articles

Hypoxia is a big concern in coastal waters as it affects ecosystem health, fishery yield, and marine water resources. Accurately modeling coastal hypoxia is still very challenging even with the most advanced numerical models. A data‐driven model for coastal water quality is proposed in this study and is applied to predict the temporal‐spatial variations of dissolved oxygen (DO) and hypoxic condition in Chesapeake Bay, the largest estuary in the United States with mean summer hypoxic zone extending about 150 km along its main axis. The proposed model has three major components including empirical orthogonal functions analysis, automatic selection of forcing …