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Articles 61 - 88 of 88
Full-Text Articles in Environmental Monitoring
Decision Process For Identification Of Estuarine Benthic Impairments, Roberto J. Llansó, Jon H. Volstad, Daniel M. Dauer
Decision Process For Identification Of Estuarine Benthic Impairments, Roberto J. Llansó, Jon H. Volstad, Daniel M. Dauer
Benthic Applications
To meet the requirements of the Clean Water Act, the States of Maryland and Virginia are in the process of developing biological criteria for evaluating estuarine waters. The Chesapeake Bay Benthic Index of Biotic Integrity (B-IBI) is the basis for these biological criteria. As an initial step, a Workgroup developed an interim framework for the application of the B-IBI to the States’ water quality inventory report (305b report) and list of impaired waters (303d list). The Workgroup included representatives of the Maryland Department of the Environment (MDE), Maryland Department of Natural Resources (MDNR), Virginia Department of Environmental Quality (DEQ), USEPA …
Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: James River (1985-2001), Daniel M. Dauer, Harold G. Marshall, Kent E. Carpenter, John R. Donat, Michael F. Lane
Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: James River (1985-2001), Daniel M. Dauer, Harold G. Marshall, Kent E. Carpenter, John R. Donat, Michael F. Lane
Status and Trends for Virginia Chesapeake Bay
This summary includes materials provided by Rick Hoffman of the Chesapeake Bay Program of the Virginia Department of Environmental Quality. Environmental information regarding other important conditions in Chesapeake Bay (e.g. submerged aquatic vegetation, fisheries, chemical contaminants) has been reported previously (Chesapeake Bay and its Tributaries: Results of Monitoring Programs And Status of Resources; 2002 Biennial Report of the Secretary of Natural Resources to The Virginia General Assembly).
The Virginia Chesapeake Bay and its tidal tributaries continue to show some environmental trends indicating progress toward restoration of a more balanced and healthy ecosystem. However, the Bay system remains degraded …
Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: Rappahannock River (1985-2001), Daniel M. Dauer, Harold G. Marshall, Kent E. Carpenter, John R. Donat, Michael F. Lane
Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: Rappahannock River (1985-2001), Daniel M. Dauer, Harold G. Marshall, Kent E. Carpenter, John R. Donat, Michael F. Lane
Status and Trends for Virginia Chesapeake Bay
This summary includes materials provided by Rick Hoffman of the Chesapeake Bay Program of the Virginia Department of Environmental Quality. Environmental information regarding other important conditions in Chesapeake Bay (e.g. submerged aquatic vegetation, fisheries, chemical contaminants) has been reported previously (Chesapeake Bay and its Tributaries: Results of Monitoring Programs And Status of Resources; 2002 Biennial Report of the Secretary of Natural Resources to The Virginia General Assembly).
The Virginia Chesapeake Bay and its tidal tributaries continue to show some environmental trends indicating progress toward restoration of a more balanced and healthy ecosystem. However, the Bay system remains degraded …
Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: York River (1985-2001), Daniel M. Dauer, Harold G. Marshall, Kent E. Carpenter, John R. Donat, Michael F. Lane
Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: York River (1985-2001), Daniel M. Dauer, Harold G. Marshall, Kent E. Carpenter, John R. Donat, Michael F. Lane
Status and Trends for Virginia Chesapeake Bay
This summary includes materials provided by Rick Hoffman of the Chesapeake Bay Program of the Virginia Department of Environmental Quality. Environmental information regarding other important conditions in Chesapeake Bay (e.g. submerged aquatic vegetation, fisheries, chemical contaminants) has been reported previously (Chesapeake Bay and its Tributaries: Results of Monitoring Programs And Status of Resources; 2002 Biennial Report of the Secretary of Natural Resources to The Virginia General Assembly).
The Virginia Chesapeake Bay and its tidal tributaries continue to show some environmental trends indicating progress toward restoration of a more balanced and healthy ecosystem. However, the Bay system remains degraded …
Effects Of Epiphyte Load On Optical Properties And Photosynthetic Potential Of The Seagrasses Thalassia Testudinum Banks Ex König And Zostera Marina L, Lisa A. Drake, Fred C. Dobbs, Richard C. Zimmerman
Effects Of Epiphyte Load On Optical Properties And Photosynthetic Potential Of The Seagrasses Thalassia Testudinum Banks Ex König And Zostera Marina L, Lisa A. Drake, Fred C. Dobbs, Richard C. Zimmerman
OES Faculty Publications
The biomass and optical properties of seagrass leaf epiphytes were measured to evaluate their potential impact on the photosynthetic performance of the seagrasses Thalassia testudinum Banks ex König (turtlegrass) and Zostera marina L. (eelgrass). Turtlegrass was obtained from oligotrophic waters near Lee Stocking Island, Bahamas; eelgrass was collected from a eutrophic environment in Monterey Bay, California. Leaf–epiphyte loads were characterized visually and quantified using measurements of their phospholipid biomass. Light absorption and reflectance of the intact epiphyte layer were determined spectrophotometrically. Turtlegrass epiphytes from the oligotrophic site absorbed a maximum of 36% of incident light in peak chlorophyll absorption …
A Biooptical Model Of Irradiance Distribution And Photosynthesis In Seagrass Canopies, Richard C. Zimmerman
A Biooptical Model Of Irradiance Distribution And Photosynthesis In Seagrass Canopies, Richard C. Zimmerman
OES Faculty Publications
Although extremely vulnerable to coastal eutrophication, seagrasses represent important structuring elements and sources of primary production in shallow waters. They also generate an optical signature that can be tracked remotely. Accurate knowledge of light absorption and scattering by submerged plant canopies permits the calculation of important plant- and ecosystem-level properties, including rates of photosynthesis, vegetation abundance, and distribution. The objectives of this study were to develop a realistic, yet simply parameterized two-flow model of plane irradiance distribution through a seagrass canopy submerged in an optically active water column, to evaluate its performance against in situ measurements, and to explore the …
Benthic Biological Monitoring Program Of The Elizabeth River Watershed (2001) With A Study Of Paradise Creek, Daniel M. Dauer
Benthic Biological Monitoring Program Of The Elizabeth River Watershed (2001) With A Study Of Paradise Creek, Daniel M. Dauer
Elizabeth River Reports
Executive Summary
A study of the macrobenthic communities of the Elizabeth River watershed was initiated in summer 1999. This report presents the data from the third year of sampling in 2001. The three objectives of the Benthic Biological Monitoring Program of the Elizabeth River watershed are: (1) To characterize the health of the tidal waters of the Elizabeth River watershed as indicated by the structure of the benthic communities. ( 2) To conduct trend analyses on long-term data at 14 fixed-point stations to relate temporal trends in the benthic communities to changes in water and/or sediment quality. Trend analyses will …
Identifying Sources Of Fecal Pollution In The Roanoke River, Roanoke County, Virginia, J. Brooks Crozier, Brian Clark, Holly Weber
Identifying Sources Of Fecal Pollution In The Roanoke River, Roanoke County, Virginia, J. Brooks Crozier, Brian Clark, Holly Weber
Virginia Journal of Science
Antibiotic Resistance Patterns (ARPs) of Enterococcus spp. were used as a phenotypic fingerprint to compare and categorize unknown-source isolates in an impaired segment of the Roanoke River, Roanoke County, Virginia. Antibiotic resistance analysis (ARA) of enterococci has been effectively used to differentiate among sources of fecal contamination in many geographic regions in the United States. Enterococcus spp. were used as a fecal indicator in a library consisting of 1,562 known-source isolates. Two-way analysis indicated that approximately 95% of the unknown-source isolates collected were of animal origin. A 3-way analysis indicated that 61% of the unknowns were of livestock origin while …
Development Of Diagnostic Approaches To Determine Sources Of Anthropogenic Stress Affecting Benthic Community Conditions In The Chesapeake Bay, Daniel M. Dauer, Michael F. Lane, Roberto J. Llansó
Development Of Diagnostic Approaches To Determine Sources Of Anthropogenic Stress Affecting Benthic Community Conditions In The Chesapeake Bay, Daniel M. Dauer, Michael F. Lane, Roberto J. Llansó
Benthic Applications
Benthic macrofauna are an important component of estuarine ecosystems. These organisms are a food source for higher trophic levels including fishes and crabs (Virnstein 1977, 1979; Holland et al. 1980; Dauer et al. 1982) and birds (Botton 1984; Quammen 1984). Benthic macrofauna affect both the physical and chemical properties of the sediment and the overlying water column (e.g., Rhoads and Young 1970; Rhoads 1973; Aller 1978, 1980), influence nutrient cycling (Rowe et al 1975; Zeiteschel 1980; Flint and Kamykowski 1984), and are capable of directly controlling phytoplankton biomass in the water column (Cleorn 1982; Officer et al 1982; Cohen et …
Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: 1985- 2000, Daniel M. Dauer, Michael F. Lane, Harold G. Marshall, Kent E. Carpenter, John R. Donat
Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: 1985- 2000, Daniel M. Dauer, Michael F. Lane, Harold G. Marshall, Kent E. Carpenter, John R. Donat
Status and Trends for Virginia Chesapeake Bay
A detailed overview of the Chesapeake Bay's living resources, water quality, and its major Virginia tributaries.
Methods For Caculating The Chesapeake Bay Benthic Index Of Biotic Integrity, Roberto J. Llansó, Daniel M. Dauer
Methods For Caculating The Chesapeake Bay Benthic Index Of Biotic Integrity, Roberto J. Llansó, Daniel M. Dauer
Benthic Applications
The Chesapeake Bay benthic index of biotic integrity (B-IBI) was developed to assess benthic community health and environmental quality in Chesapeake Bay. The B-IBI evaluates the ecological condition of a sample by comparing values of key benthic community attributes (“metrics”) to reference values expected under non-degraded conditions in similar habitat types. It is therefore a measure of deviation from reference conditions.
The B-IBI is used by the Chesapeake Bay Benthic Monitoring Program, which is conducted by the Maryland Department of Natural Resources (MD DNR) and by the Virginia Department of Environmental Quality (VA DEQ). The program contains two primary elements: …
Benthic Biological Monitoring Program Of The Elizabeth River Watershed (2000), Daniel M. Dauer
Benthic Biological Monitoring Program Of The Elizabeth River Watershed (2000), Daniel M. Dauer
Elizabeth River Reports
Executive Summary
A study of the macrobenthic communities of the Elizabeth River watershed was initiated in summer 1999. This report presents the data from the second year of sampling in 2000. The three objectives of the Benthic Biological Monitoring Program of the Elizabeth River watershed are: (1) To characterize the health of the tidal waters of the Elizabeth River watershed as indicated by the structure of the benthic communities. ( 2) To conduct trend analyses on long-term data at 14 fixed-point stations to relate temporal trends in the benthic communities to changes in water and/or sediment quality. Trend analyses will …
A Comparison Of Phytoplankton Communities In Lake Prince And The Western Branch Reservoir, Suffolk, Virginia, Cara Marie Muscio
A Comparison Of Phytoplankton Communities In Lake Prince And The Western Branch Reservoir, Suffolk, Virginia, Cara Marie Muscio
Biological Sciences Theses & Dissertations
Lake Prince and the Western Branch Reservoir are two eutrophic bodies of water located in Suffolk, Virginia. Lake Prince and its two small tributaries join the Western branch via a constructed spillway. This lake system is a source of water for the surrounding municipalities, and a recreational area for community citizens. In the past, these bodies of water had repeated incidents of low oxygen and nuisance algal blooms, particularly cyanobacteria species. As a result aerators have been installed in the main body of both Lake Prince and the Western Branch Reservoir. In addition, a pipeline has been installed from North …
Effects Of Human Disturbances On The Behavior Of Dabbling Ducks, Melissa Lynn Pease
Effects Of Human Disturbances On The Behavior Of Dabbling Ducks, Melissa Lynn Pease
Biological Sciences Theses & Dissertations
Disturbance of wintering and migrating birds by human activities can cause birds to expend energy in avoidance of humans and reduces the time available for resting and feeding at a time in the annual cycle when fat deposition and energy conservation are important. Also, human disturbances can effectively cause habitat loss by displacing birds from feeding or resting habitat. Managers of natural resources are increasingly faced with decisions about the types and amounts of public use that should be allowed without lowering the value of the resource for wildlife. In order for managers to make decisions about how to minimize …
Effects Of Collection, Transport, And Redeployment Methods On Natural Mortality Of Rangia Cuneata (Mactridae) Used In Biomonitoring Studies, Eugene G. Maurakis, David V. Grimes, William C. Gretes
Effects Of Collection, Transport, And Redeployment Methods On Natural Mortality Of Rangia Cuneata (Mactridae) Used In Biomonitoring Studies, Eugene G. Maurakis, David V. Grimes, William C. Gretes
Virginia Journal of Science
Sporadic, high mortality in test populations of wedge clams (Rangia cuneata) has limited the potential for using this otherwise desirable test organism in biomonitoring studies. To determine whether high mortality was due to ontogenic or experimental variables, a two-phased study was conducted. In phase I, mortality of collected and re-deployed wedge clams, subjected to varying transport conditions, was determined at 7, 14, 21 and 60 days re-deployment. The use of three transport times (1, 2, 3 hr.), two vehicle conditions (open, closed) and three transport treatments (open, closed, iced containers) yielded 18 test groups. Individual test group mortalities …
Benthic Biological Monitoring Program Of The Elizabeth River Watershed (1999), Daniel M. Dauer
Benthic Biological Monitoring Program Of The Elizabeth River Watershed (1999), Daniel M. Dauer
Elizabeth River Reports
Executive Summary
A study of the macrobenthic communities of the Elizabeth River watershed was conducted in summer 1999. The three objectives of the Benthic Biological Monitoring Program of the Elizabeth River watershed are: (1) To characterize the health of regional areas of the tidal waters of the Elizabeth River watershed Chesapeake Bay as indicated by the structure of the benthic communities. These characterizations are based upon application of benthic restoration goals and the Benthic Index of Biotic Integrity (BIBI) developed for the Chesapeake Bay to five primary strata - the Mainstem of the river, the Lafayette River, the Southern Branch, …
Stomach Content Analysis Of Stranded Bottlenose Dolphins, Tursiops Truncatus, In Virginia, 1987-1996, John Mcgurk
Stomach Content Analysis Of Stranded Bottlenose Dolphins, Tursiops Truncatus, In Virginia, 1987-1996, John Mcgurk
Biological Sciences Theses & Dissertations
I examined the stomach contents from 94 bottlenose dolphins, Tursiops truncatus, that were stranded along the Virginia coastline from 1987 through 1996. Samples from 1987 through 1991 were obtained from the National Museum of Natural History (NMNH) and samples from 1992 through 1996 were collected by the Virginia Marine Science Museum (VMSM) Stranding Team. Prey species were identified using fish otoliths and cephalopod beaks.
The dolphins examined fed on 23 species of fish and one genus of cephalopods. The primary prey species was Atlantic croaker (Micropogonias undulatus); secondary species were weakfish (Cynoscion regalia), spot (Leiostomus xanthurus), silver perch (Bairdiella chrysoura), …
Zooplankton Community Dynamics In The Elizabeth River, Virginia, William C. Sharp
Zooplankton Community Dynamics In The Elizabeth River, Virginia, William C. Sharp
Biological Sciences Theses & Dissertations
Zooplankton community structure and dynamics were studied over a 12 month period in the Elizabeth River, an industrially polluted tidal river in the Chesapeake Bay estuarine system. An additional site in this estuary (Hampton Roads) was sampled for comparative purposes. Multivariate analysis indicated five distinct temporal groups occurred during the year, but there were no significant differences in spatial composition within the river. Maximum zooplankton concentrations were observed in July and lowest abundances were observed in February, March, and November. Copepods, especially Acartia species, were the most abundant components of the zooplankton community, comprising 67 to 93% of the total …
Molecular And Physiological Responses Of Diatoms To Variable Levels Of Irradiance And Nitrogen Availability: Growth Of Skeletonema Costatum In Simulated Upwelling Conditions, G. Jason Smith, Richard C. Zimmerman, Randall S. Alberte
Molecular And Physiological Responses Of Diatoms To Variable Levels Of Irradiance And Nitrogen Availability: Growth Of Skeletonema Costatum In Simulated Upwelling Conditions, G. Jason Smith, Richard C. Zimmerman, Randall S. Alberte
OES Faculty Publications
Molecular mechanisms that drive metabolic acclimation to environmental shifts have been poorly characterized in phytoplankton. In this laboratory study. the response of light- and N-limited Skeletonema costatum cells to an increase in light and NO3 availability was examined. C assimilation was depressed relative to N assimilation early in enrichment, and the photosynthetic quotient (O2: CO2) increased, consistent with the shunting of reducing equivalents from CO2 fixation to NO3- reduction. The concomitant increase in dark respiration was consistent with the increased energetic demand associated with macromolecular synthesis. The accelerations of N-specific rates of …
Assessment Of Organic And Metal Contaminants In Lower Back Bay And Upper Currituck Sound, Kate Benkert
Assessment Of Organic And Metal Contaminants In Lower Back Bay And Upper Currituck Sound, Kate Benkert
V. Poster Abstracts
Studies were conducted at Mackay Island National Wildlife Refuge in 1988 and 1989 to provide baseline data for an assessment of organic chemicals and metal contaminants in the aquatic ecosystem. Longnose gar, gizzard shad, snapping turtles, common rangia clams and sediments were collected from sites in lower Back Bay and upper Currituck Sound for contaminant analyses.
Composite sediment samples were analyzed for the presence of metals, organochlorine pesticides and polycyclic aromatic hydrocarbons (PAHs). Organochlorine pesticides were not detected in the sediments. Various PAH compounds were detected in the sediments, although at trace concentrations which just exceeded the analytical detection limit …
Hydrogeology And Water Budget Analysis Of Two Interdunal Ponds Nags Head Woods Ecological Preserve, Dare County, North Carolina, Richard A. Hisert
Hydrogeology And Water Budget Analysis Of Two Interdunal Ponds Nags Head Woods Ecological Preserve, Dare County, North Carolina, Richard A. Hisert
OES Theses and Dissertations
Ground-water-fed interdunal ponds in Nags Head Woods Ecological Preserve lose as much as 7600 m3 yr-1 of water through evaporation. This withdrawal of groundwater is sufficient to significantly alter flow patterns through the surficial aquifer on Bodie Island, N.C. Statistical analyses of evaporation estimates derived by various methods indicate a weak correlation, (r2=0.4-0.5) between pan evaporation data from Aurora, N.C. and pond evaporation at Nags Head Woods calculated by water budget analyses.
Results of stratigraphic and pedologic analyses in and around the ponds indicate that the ponds formed after development of multiple generations of dunes. This …
Acceleration Of Nutrient Uptake By Phytoplankton In A Coastal Upwelling Ecosystem: A Modeling Analysis, Richard C. Zimmerman, James N. Kremer, Richard C. Dugdale
Acceleration Of Nutrient Uptake By Phytoplankton In A Coastal Upwelling Ecosystem: A Modeling Analysis, Richard C. Zimmerman, James N. Kremer, Richard C. Dugdale
OES Faculty Publications
Studies of upwelling centers in the eastern Pacific suggest that maximum rates of nitrate uptake (light and nutrient saturated) increase, or shift-up, as newly upwelled water moves downstream. The rate of shift-up appears to be related to irradiance and the ambient concentration of limiting nutrient at the time of upwelling. A mathematical model was developed to evaluate effects of irradiance and initial nitrate concentration on temporal patterns of shift-up and subsequent time scales of nutrient utilization over a range of simulated upwelling conditions. When rates consistent with field studies were used, complete shift-up was possible only under certain conditions, and …
Effects Of El Nino On Local Hydrography And Growth Of The Giant Kelp, Macrocystis Pyrifera, At Santa Catalina Island, California, Richard C. Zimmerman, Deborah L. Robertson
Effects Of El Nino On Local Hydrography And Growth Of The Giant Kelp, Macrocystis Pyrifera, At Santa Catalina Island, California, Richard C. Zimmerman, Deborah L. Robertson
OES Faculty Publications
Deepened isotherms associated with El Niño resulted in severe nutrient limitation and very low kelp productivity during the last half of 1983. Frond growth rates were so low that terminal blades formed before reaching the surface, eliminating the canopy. Frond initiation rates were also extremely low, resulting in significant reductions in mean plant size. Plants growing above 10m were more severely affected than plants at 20m. Nutrient pulses associated with internal waves are thus critical for survival of Macrocystis pyrifera in nutritionally marginal habitats in Southern California.
Input And Distribution Of Sewage Derived Sedimentary Material Adjacent To Chesapeake-Elizabeth Sewage Outfall, Virginia Beach, Virginia, Robert Carroll Brown
Input And Distribution Of Sewage Derived Sedimentary Material Adjacent To Chesapeake-Elizabeth Sewage Outfall, Virginia Beach, Virginia, Robert Carroll Brown
OES Theses and Dissertations
The concentrations of coprostanol and hydrocarbons were measured in the effluent from the Chesapeake-Elizabeth sewage treatment plant and surface sediments from the area surrounding the effluent discharge site. Most of the coprostanol (>84%) and hydrocarbons (>91%) were associated with particulates in the effluent. Some of these particles were incorporated into the sedimentary column within the study area, while some may have escaped from the area.
The study area is found to be a dynamic area where changes in the percentage and distribution of fine-grained sediments occur over periods of months. The movement of fine-grained sediments is an important …
Litter Production And Nutrient Content Of Litter In The Seasonally Flooded Dismal Swamp, Marta M. Gomez
Litter Production And Nutrient Content Of Litter In The Seasonally Flooded Dismal Swamp, Marta M. Gomez
Biological Sciences Theses & Dissertations
Litter production was studied in four plant communities in the Great Dismal Swamp, Virginia, that differ primarily in species composition and flooding regime. Greatest leaf deposition occurred in the more flooded communities, maple-gum (Acer-Nyssa) with 536 g m-2 yr-1 and cypress (Taxodium distichum (L.) Richard) with 528 g m-2 yr-1, followed by the cedar (Chamaecyparis thyoides (L.) BSP) and mixed hardwood (Quercus-Acer-Nyssa-Liquidambar) communities with 506 g m-2 yr-1 and 455 g m-2 yr-1, respectively. Litter nutrient concentrations were generally higher in the cypress and maple-gum stands, indicating greater nutrient availability …
Macrobenthic Communities Of An Industrialized Seaport Ecosystem: The Southern Branch Of The Elizabeth River, Virginia, Steven D. Hawthorne
Macrobenthic Communities Of An Industrialized Seaport Ecosystem: The Southern Branch Of The Elizabeth River, Virginia, Steven D. Hawthorne
Biological Sciences Theses & Dissertations
Macrobenthic invertebrates of an industrialized seaport ecosystem were studied seasonally from October, 1977 through July, 1978. Five stations were selected along the Southern Branch of the Elizabeth River, Virginia. The stations ranged from an area of heavy industrialization to a non-urbanized environment. At each station, bottom water was measured for salinity, temperature, dissolved oxygen, and pH. Within each sampling area, macrobenthic infauna! invertebrates were collected from in and out of channel sites along with sediment samples for various types of physicochemical analysis.
Community structure was spatially homogeneous at station sites and throughout the stations along the River. Slightly acidic pH …
Application Of Satellite Data And Lars' Data Processing Techniques To Mapping Vegetation Of The Dismal Swamp, Jeffrey Allan Messmore
Application Of Satellite Data And Lars' Data Processing Techniques To Mapping Vegetation Of The Dismal Swamp, Jeffrey Allan Messmore
Biological Sciences Theses & Dissertations
This study concerned the feasibility of using digital satellite imagery and automatic data processing (ADP) techniques as a means of mapping swamp forest vegetation. Multispectral scanner data acquired by the Earth Resources Technology Satellite (ERTS-1; renamed LANDSAT-1) was analyzed using ADP techniques developed by Purdue University's Laboratory for Applications of Remote Sensing (LARS). The site for this investigation was the Dismal Swamp, a 210,000 acre swamp forest located south of Suffolk, Va. on the Virginia-North Carolina border. Two basic classification strategies were employed in determining the vegetation mapping capability of ERTS-1 data. The initial classification utilized unsupervised techniques which produced …
The Occurrence And Distribution Of Methane In The Marine Environment, Larry P. Atkinson, Francis A. Richards
The Occurrence And Distribution Of Methane In The Marine Environment, Larry P. Atkinson, Francis A. Richards
CCPO Publications
The distributions of methane dissolved in the sulfide-bearing waters of the Black Sea, the Cariaco Trench, and Lake Nitinat are reported. The gas was not detected in the oxygen-deficient water of the eastern tropical Pacific Ocean, in the Santa Barbara Basin, nor in the sulfide-bearing water of Saanich Inlet. Maximum concentrations observed were 70 μmole CH4/l., and the distribution tends to follow that of sulfide. The data indicate that methane is derived from organic compounds not containing nitrogen or phosphorus and that its formation is much slower than that of sulfide. The solubility coefficient in seawater (salinity = 40‰) is …