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Full-Text Articles in Fresh Water Studies

Improved Estimates Of Tributary Nitrogen Load To Casco Bay, Maine, Whitley J. Gray Aug 2019

Improved Estimates Of Tributary Nitrogen Load To Casco Bay, Maine, Whitley J. Gray

Electronic Theses and Dissertations

Over the past two decades, total nitrogen (TN) concentrations have increased in Casco Bay (CBEP 2015). The sources of the increased nitrogen are poorly understood but occur with simultaneous population growth and land use changes. The total riverine nitrogen load to Casco Bay was previously estimated by Liebman and Milstead (2012) using the United States Geologic Survey’s (USGS) SPAtially Referenced Regression On Watershed attributes (SPARROW) model. The SPARROW model uses watershed characteristics, regional monitoring data and nitrogen source data to estimate nitrogen loading but was not validated using measurements of nitrogen in the Casco Bay watershed. This study attempts to …


Estuarine Dissolved Organic Carbon Flux From Space: With Application To Chesapeake And Delaware Bays, Sergio R. Signorini, Antonio Mannino, Marjorie A.M. Friedrichs, Pierre St-Laurent, John Wilkin, Aboozar Tabatabai, Raymond G. Najjar, Eileen E. Hofmann, Fei Da, Hanqin Tian, Yuanzhi Yao Jun 2019

Estuarine Dissolved Organic Carbon Flux From Space: With Application To Chesapeake And Delaware Bays, Sergio R. Signorini, Antonio Mannino, Marjorie A.M. Friedrichs, Pierre St-Laurent, John Wilkin, Aboozar Tabatabai, Raymond G. Najjar, Eileen E. Hofmann, Fei Da, Hanqin Tian, Yuanzhi Yao

CCPO Publications

This study uses a neural network model trained with in situ data, combined with satellite data and hydrodynamic model products, to compute the daily estuarine export of dissolved organic carbon (DOC) at the mouths of Chesapeake Bay (CB) and Delaware Bay (DB) from 2007 to 2011. Both bays show large flux variability with highest fluxes in spring and lowest in fall as well as interannual flux variability (0.18 and 0.27 Tg C/year in 2008 and 2010 for CB; 0.04 and 0.09 Tg C/year in 2008 and 2011 for DB). Based on previous estimates of total organic carbon (TOCexp) exported by …


Stable Isotope Analysis Reveals Different Trophic Niche Spaces For Wild And Hatchery Origin Juvenile Chinook Salmon In The Nisqually Delta, Melanie Davis, Isa Woo, Christopher S. Ellings, Sayre Hodgson, Susan De La Cruz Apr 2018

Stable Isotope Analysis Reveals Different Trophic Niche Spaces For Wild And Hatchery Origin Juvenile Chinook Salmon In The Nisqually Delta, Melanie Davis, Isa Woo, Christopher S. Ellings, Sayre Hodgson, Susan De La Cruz

Salish Sea Ecosystem Conference

Hatchery programs have been used as a conservation tool to bolster declining Chinook salmon (Oncorhynchus tshawytscha) populations throughout much of the Salish Sea. In many watersheds, hatchery fish are released concurrently with the natural-origin population, thus raising the potential for density dependent effects via depleted prey resources, territorial behavior, and movement into sub-optimal habitats. Competition during the critical period for early marine growth and survival might have detrimental effects for wild Chinook salmon populations, highlighting the potential importance of a productive delta habitat mosaic. We used an integrated diet approach with stomach content and stable isotope analyses to evaluate differential …


Lessons From Cumulative Effects Assessment And Management Initiatives On The North Pacific Coast Of British Columbia, Rebecca Martone, John Bones, Steve Diggon, Stuart Crawford, Maya Paul, Gord Mcgee Apr 2018

Lessons From Cumulative Effects Assessment And Management Initiatives On The North Pacific Coast Of British Columbia, Rebecca Martone, John Bones, Steve Diggon, Stuart Crawford, Maya Paul, Gord Mcgee

Salish Sea Ecosystem Conference

The Marine Plan Partnership (MaPP) is a collaborative, government-to-government initiative between the Province of British Columbia and 17 member First Nations in an area that encompasses approximately 102,000 km2 along two-thirds of British Columbia’s coast. Between 2011 and 2016, the Partners worked together complete a set of comprehensive marine plans for four sub-regions and an accompanying Regional Action Framework (RAF) emphasizing ecosystem-based management (EBM) of coastal and marine ecosystems and resources. MaPP sub-regional plans and the RAF inform decisions on the sustainable economic development and stewardship of the North Pacific Coast’s ecosystems by providing recommendations for key areas of marine …


A Centennial Record Of Paleosalinity Change In The Tidal Reaches Of The Potomac And Rappahannock Rivers, Tributaries To Chesapeake Bay, Neil E. Tibert, Lindsay J. Walker, William P. Patterson, J. Bradford Hubeny, Emma Jones, Olivia R. Cooper Oct 2012

A Centennial Record Of Paleosalinity Change In The Tidal Reaches Of The Potomac And Rappahannock Rivers, Tributaries To Chesapeake Bay, Neil E. Tibert, Lindsay J. Walker, William P. Patterson, J. Bradford Hubeny, Emma Jones, Olivia R. Cooper

Virginia Journal of Science

Gravity and push cores from the Potomac and Rappahannock Rivers (Virginia Tidewater) were collected from central and proximal estuarine zones with known seasonal salinity stratification. The lowermost microfossil associations in the cores comprise alternating ostracode populations of Cyprideis salebrosa and Cytheromorpha. This microfossil association gives way to an oligohaline association dominated by the freshwater ostracode Darwinula stevensoni. Stable oxygen isotope values (δ18O) of Rapphannock Cyprideis salebrosa are highly variable ranging between -6.6 to -3.2‰ VPDB. δ18O values for Potomac Cytheromorpha fuscata range from -8.2 to -3.2‰ VPDB. Positive excursions in δ18O values …


Simulation Of Coastal Inundation Instigated By Storm Surge And River Discharge In The Chesapeake Bay Using Sub-Grid Modeling Coupled With Lidar Data, J. D. Loftis, H. V. Wang Jan 2012

Simulation Of Coastal Inundation Instigated By Storm Surge And River Discharge In The Chesapeake Bay Using Sub-Grid Modeling Coupled With Lidar Data, J. D. Loftis, H. V. Wang

Presentations

Sub-grid modeling is a novel method by which water level elevations on the sub-grid level can be obtained through the combination of water levels and velocities efficiently calculated at the coarse computational grid, the discretized bathymetric depths, and local friction parameters without resorting to solve the full set of equations. Sub-grid technology essentially allows velocity to be determined rationally and efficiently at the sub-grid level. This salient feature enables coastal flooding to be addressed in a single cross-scale model from the ocean to the upstream river channel without overly refining the grid resolution. To this end, high-resolution DEMs will be …


Fortnightly Variability At The Transition Between Two Sub-Estuaries, Mayra Lorena Riveron Enzastiga Jul 2006

Fortnightly Variability At The Transition Between Two Sub-Estuaries, Mayra Lorena Riveron Enzastiga

OES Theses and Dissertations

Profiles of current velocity from an Acoustic Doppler Current Profiler (ADCP) and of water salinity, temperature and density from a Conductivity-Temperature-Depth (CTD) recorder, were combined with surface salinity, temperature and density from a Conductivity-Temperature (CT) recorder to elucidate the fortnightly variability at the Lafayette River entrance. The Lafayette River connects at its mouth with the Elizabeth River, which is a tributary to the James River in the Chesapeake Bay. Data were collected in four experiments during consecutive spring and neap tides in the autumn of 2000, and in the spring of 2001. Each experiment was carried out for -25 hours …


A Preliminary Survey Of The Damariscotta River Estuary, Lincoln County, Maine, Maine Department Of Economic Development Jun 1970

A Preliminary Survey Of The Damariscotta River Estuary, Lincoln County, Maine, Maine Department Of Economic Development

Maine Collection

A Preliminary Survey of the Damariscotta River Estuary, Lincoln County, Maine

Part I - Hydrology; Part II - Sediments

"Prepared Under a Grant From the Maine Marine Stipend Program".

Maine Department of Economic Development - Division of Science, Technology & Mineral Resources, Augusta, Maine (July 1969 - June 1970).