In 1994, a multi-year study was initiated to determine the feasibility as well as the environment... more In 1994, a multi-year study was initiated to determine the feasibility as well as the environmental acceptability of using pellets produced from fly ash from Virginia Power`s Chesapeake Energy Center (CEC). The intent of the study was to demonstrate a beneficial use for the fly ash that would compensate for natural reef losses by providing an alternate substrate for oyster attachment in the Chesapeake Bay. The results of the study indicate that pellets made from a mixture of approximately 88% CEC fly ash and 12% Type II Portland Cement are environmentally safe and facilitate the settlement, attachment and growth of oysters.
Journal of Experimental Marine Biology and Ecology, 1989
... and particle flux on growth rates of juvenile bay scallops Argopecten irradians Jennifer A. C... more ... and particle flux on growth rates of juvenile bay scallops Argopecten irradians Jennifer A. Cahalan, Scott E. Siddall and Mark W. Luckenbach ... Growth rates within populations of bivalves have been positively correlated to food fluxes in field situations (Wildish & Kristmanson, 1985 ...
Keywords: water quality nitrogen cycle oyster reefs oyster culture denitrification Crassostrea vi... more Keywords: water quality nitrogen cycle oyster reefs oyster culture denitrification Crassostrea virginica a b s t r a c t Enhancing populations of suspension feeding bivalves, particularly the eastern oyster, Crassostrea virginica, has been proposed as a means of mitigating eutrophication in coastal waters. Review of studies evaluating the effects of C. virginica on nitrogen (N) cycling found that oysters can have effects on water quality that vary by orders of magnitude among sites, seasons, and growing condition (e.g., oyster reefs, aquaculture). Nitrogen contained in phytoplankton consumed by oysters may be returned to the water column, assimilated into oyster tissue and shell, buried in the sediments, or returned to the atmosphere as dinitrogen gas, primarily via denitrification. Accurately quantifying oyster-related N removal requires detailed knowledge of these primary fates of N in coastal waters. A review of existing data demonstrated that the current state of knowledge is incomplete in many respects. Nitrogen assimilated into oyster tissue and shell per gram of dry weight was generally similar across sites and in oysters growing on reefs compared to aquaculture. Data on long-term burial of N associated with oyster reefs or aquaculture are lacking. When compared to suitable reference sites, denitrification rates were not consistently enhanced. Depending on environmental and oyster growing conditions, changes in denitrification rates varied by orders of magnitude among studies and did not always occur. Oyster aquaculture rarely enhanced denitrification. Unharvested oyster reefs frequently enhanced denitrification rates. Incorporating oysters into nutrient reduction strategies will require filling gaps in existing data to determine the extent to which relationships between N removal and environmental and/or growing conditions can be generalized. The widespread eutrophication of coastal waters clearly involves increased nitrogen loads, in most cases with nitrogen derived from human activities within contributing watersheds. This has prompted regulators, managers, and other stakeholders to set standards for water quality that involve lowering nitrogen loads to estuaries and other coastal waters. To carry out the proscribed lowering of nitrogen loads there are a number of options. In many instances and sites with high human density and intense activity, advanced wastewater treatment plants are unavoidable, but such environmental engineering approaches are costly. There are many coastal zones with lower population densities where other, less costly alternative strategies might be less expensive and more attuned to " green " approaches. In this issue Kellogg and many colleagues report the results of a workshop aimed at assessment of the potential of one such alternative, the use of shellfish as a way to intercept and remove nitrogen from within estuaries exposed to increased nitrogen loads from watersheds.
... Heather D. Harwell, 1 * Peter R. Kingsley-Smith, 1 † M. Lisa Kellogg, 2 Steven M. Allen, 3 ‡ ... more ... Heather D. Harwell, 1 * Peter R. Kingsley-Smith, 1 † M. Lisa Kellogg, 2 Steven M. Allen, 3 ‡ Standish K. Allen, Jr., 4 Donald W. Meritt, 3 Kennedy T. Paynter, Jr., 3, 5 and Mark W. Luckenbach 1. ... (A) Severn. (B) Patuxent. (C) York. (D) Machipongo. ...
The ABC method for evaluating pollution-induced stress was tested using data from the Chesapeake ... more The ABC method for evaluating pollution-induced stress was tested using data from the Chesapeake Bay, Virginia, collected between 1985 and 1989. Three predictions were tested: (1) benthic communities from estuarine transitional regions with salinities near the range of 5 to 8 parts per thousand (horohalinicium) should be classified highly stressed due to major shifts in ionic composition producing physiological stress;
Journal of Experimental Marine Biology and Ecology, 1987
... RJ Feller, SE Stancyk, SA Woodin and two anonymous reviewers provided valuable comments on th... more ... RJ Feller, SE Stancyk, SA Woodin and two anonymous reviewers provided valuable comments on the manuscript. REFERENCES AMBROSE, WG, JR., 1984. ... 67, pp.661-677. ECKMAN,JE, ARM NOWELL & PA JUMARS, 1981. Sediment destabilization by animal tubes. J. Mar. ...
The costs and benefits of non-native introductions as a restoration tool should be estimated prio... more The costs and benefits of non-native introductions as a restoration tool should be estimated prior to any action to prevent both undesirable consequences and waste of restoration resources. The suggested introduction of non-native oyster species, Crassostrea ariakensis, into Chesapeake Bay, USA, provides a good example in which the survival of non-native oysters may differ from that of native oysters, Crassostrea
Many of the world&#39... more Many of the world's coastal ecosystems are impacted by multiple stressors each of which may be subject to different management strategies that may have overlapping or even conflicting objectives. Consequently, management results may be indirect and difficult to predict or observe. We developed a network simulation model intended specifically to examine ecosystem-level responses to management and applied this model to a comparison of nutrient load reduction and restoration of highly reduced stocks of bivalve suspension feeders (eastern oyster, Crassostrea virginica) in an estuarine ecosystem (Chesapeake Bay, USA). Model results suggest that a 50% reduction in nutrient inputs from the watershed will result in lower phytoplankton production in the spring and reduced delivery of organic material to the benthos that will limit spring and summer pelagic secondary production. The model predicts that low levels of oyster restoration will have no effect in the spring but does result in a reduction in phytoplankton standing stocks in the summer. Both actions have a negative effect on pelagic secondary production, but the predicted effect of oyster restoration is larger. The lower effect of oysters on phytoplankton is due to size-based differences in filtration efficiency and seasonality that result in maximum top-down grazer control of oysters at a time when the phytoplankton is already subject to heavy grazing. These results suggest that oyster restoration must be achieved at levels as much as 25-fold present biomass to have a meaningful effect on phytoplankton biomass and as much as 50-fold to achieve effects similar to a 50% nutrient load reduction. The unintended effect of oyster restoration at these levels on other consumers represents a trade-off to the desired effect of reversing eutrophication.
In 1994, a multi-year study was initiated to determine the feasibility as well as the environment... more In 1994, a multi-year study was initiated to determine the feasibility as well as the environmental acceptability of using pellets produced from fly ash from Virginia Power`s Chesapeake Energy Center (CEC). The intent of the study was to demonstrate a beneficial use for the fly ash that would compensate for natural reef losses by providing an alternate substrate for oyster attachment in the Chesapeake Bay. The results of the study indicate that pellets made from a mixture of approximately 88% CEC fly ash and 12% Type II Portland Cement are environmentally safe and facilitate the settlement, attachment and growth of oysters.
Journal of Experimental Marine Biology and Ecology, 1989
... and particle flux on growth rates of juvenile bay scallops Argopecten irradians Jennifer A. C... more ... and particle flux on growth rates of juvenile bay scallops Argopecten irradians Jennifer A. Cahalan, Scott E. Siddall and Mark W. Luckenbach ... Growth rates within populations of bivalves have been positively correlated to food fluxes in field situations (Wildish & Kristmanson, 1985 ...
Keywords: water quality nitrogen cycle oyster reefs oyster culture denitrification Crassostrea vi... more Keywords: water quality nitrogen cycle oyster reefs oyster culture denitrification Crassostrea virginica a b s t r a c t Enhancing populations of suspension feeding bivalves, particularly the eastern oyster, Crassostrea virginica, has been proposed as a means of mitigating eutrophication in coastal waters. Review of studies evaluating the effects of C. virginica on nitrogen (N) cycling found that oysters can have effects on water quality that vary by orders of magnitude among sites, seasons, and growing condition (e.g., oyster reefs, aquaculture). Nitrogen contained in phytoplankton consumed by oysters may be returned to the water column, assimilated into oyster tissue and shell, buried in the sediments, or returned to the atmosphere as dinitrogen gas, primarily via denitrification. Accurately quantifying oyster-related N removal requires detailed knowledge of these primary fates of N in coastal waters. A review of existing data demonstrated that the current state of knowledge is incomplete in many respects. Nitrogen assimilated into oyster tissue and shell per gram of dry weight was generally similar across sites and in oysters growing on reefs compared to aquaculture. Data on long-term burial of N associated with oyster reefs or aquaculture are lacking. When compared to suitable reference sites, denitrification rates were not consistently enhanced. Depending on environmental and oyster growing conditions, changes in denitrification rates varied by orders of magnitude among studies and did not always occur. Oyster aquaculture rarely enhanced denitrification. Unharvested oyster reefs frequently enhanced denitrification rates. Incorporating oysters into nutrient reduction strategies will require filling gaps in existing data to determine the extent to which relationships between N removal and environmental and/or growing conditions can be generalized. The widespread eutrophication of coastal waters clearly involves increased nitrogen loads, in most cases with nitrogen derived from human activities within contributing watersheds. This has prompted regulators, managers, and other stakeholders to set standards for water quality that involve lowering nitrogen loads to estuaries and other coastal waters. To carry out the proscribed lowering of nitrogen loads there are a number of options. In many instances and sites with high human density and intense activity, advanced wastewater treatment plants are unavoidable, but such environmental engineering approaches are costly. There are many coastal zones with lower population densities where other, less costly alternative strategies might be less expensive and more attuned to " green " approaches. In this issue Kellogg and many colleagues report the results of a workshop aimed at assessment of the potential of one such alternative, the use of shellfish as a way to intercept and remove nitrogen from within estuaries exposed to increased nitrogen loads from watersheds.
... Heather D. Harwell, 1 * Peter R. Kingsley-Smith, 1 † M. Lisa Kellogg, 2 Steven M. Allen, 3 ‡ ... more ... Heather D. Harwell, 1 * Peter R. Kingsley-Smith, 1 † M. Lisa Kellogg, 2 Steven M. Allen, 3 ‡ Standish K. Allen, Jr., 4 Donald W. Meritt, 3 Kennedy T. Paynter, Jr., 3, 5 and Mark W. Luckenbach 1. ... (A) Severn. (B) Patuxent. (C) York. (D) Machipongo. ...
The ABC method for evaluating pollution-induced stress was tested using data from the Chesapeake ... more The ABC method for evaluating pollution-induced stress was tested using data from the Chesapeake Bay, Virginia, collected between 1985 and 1989. Three predictions were tested: (1) benthic communities from estuarine transitional regions with salinities near the range of 5 to 8 parts per thousand (horohalinicium) should be classified highly stressed due to major shifts in ionic composition producing physiological stress;
Journal of Experimental Marine Biology and Ecology, 1987
... RJ Feller, SE Stancyk, SA Woodin and two anonymous reviewers provided valuable comments on th... more ... RJ Feller, SE Stancyk, SA Woodin and two anonymous reviewers provided valuable comments on the manuscript. REFERENCES AMBROSE, WG, JR., 1984. ... 67, pp.661-677. ECKMAN,JE, ARM NOWELL & PA JUMARS, 1981. Sediment destabilization by animal tubes. J. Mar. ...
The costs and benefits of non-native introductions as a restoration tool should be estimated prio... more The costs and benefits of non-native introductions as a restoration tool should be estimated prior to any action to prevent both undesirable consequences and waste of restoration resources. The suggested introduction of non-native oyster species, Crassostrea ariakensis, into Chesapeake Bay, USA, provides a good example in which the survival of non-native oysters may differ from that of native oysters, Crassostrea
Many of the world&#39... more Many of the world's coastal ecosystems are impacted by multiple stressors each of which may be subject to different management strategies that may have overlapping or even conflicting objectives. Consequently, management results may be indirect and difficult to predict or observe. We developed a network simulation model intended specifically to examine ecosystem-level responses to management and applied this model to a comparison of nutrient load reduction and restoration of highly reduced stocks of bivalve suspension feeders (eastern oyster, Crassostrea virginica) in an estuarine ecosystem (Chesapeake Bay, USA). Model results suggest that a 50% reduction in nutrient inputs from the watershed will result in lower phytoplankton production in the spring and reduced delivery of organic material to the benthos that will limit spring and summer pelagic secondary production. The model predicts that low levels of oyster restoration will have no effect in the spring but does result in a reduction in phytoplankton standing stocks in the summer. Both actions have a negative effect on pelagic secondary production, but the predicted effect of oyster restoration is larger. The lower effect of oysters on phytoplankton is due to size-based differences in filtration efficiency and seasonality that result in maximum top-down grazer control of oysters at a time when the phytoplankton is already subject to heavy grazing. These results suggest that oyster restoration must be achieved at levels as much as 25-fold present biomass to have a meaningful effect on phytoplankton biomass and as much as 50-fold to achieve effects similar to a 50% nutrient load reduction. The unintended effect of oyster restoration at these levels on other consumers represents a trade-off to the desired effect of reversing eutrophication.
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