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1.
The rapid rate of development in the South Carolina (SC) coastal zone has heightened public concern for the condition of the state's estuaries, and alerted scientists to the potential that novel and adverse effects on estuarine ecosystems may result. Although well-developed databases from long-term monitoring programs exist for many variables valuable in predicting and following system responses, information on phytoplankton distributions in SC estuaries has lagged. Knowledge of the dynamical relationship between environmental (e.g., nutrient quantity and quality) and biological (e.g., grazing) regulation, and phytoplankton biomass and composition is critical to understanding estuarine susceptibility to eutrophication or harmful algal blooms (HABs). Recently, SC scientists from federal, state, and academic institutions established a collaborative monitoring program to assess HAB distribution and ecology statewide. The South Carolina Harmful Algal Bloom Program includes: a) intensive temporal monitoring at areas of known HAB occurrence or those exhibiting symptoms potentially related to HABs (e.g., prevalent fish lesions), b) extensive spatial monitoring in coordination with existing statewide efforts, c) a citizen volunteer monitoring network, d) nutrient response bioassays, and e) laboratory-based physiological experiments on HAB isolates. By combining trip-wire surveillance and rapid response systems, routine monitoring of environmental parameters and HAB distribution, and process-oriented studies examining the physiological functioning of HAB species, an enhanced understanding of the impact and environmental control of HABs in SC estuaries will be achieved. The application of this approach to studies on the distribution and physiological ecology of a new widespread SC red tide, and to the discovery of several potentially toxic blooms (including Pfiesteria) in SC holding ponds, are described.  相似文献   

2.
The South Carolina Estuarine and Coastal Assessment Program (SCECAP) was initiated in 1999 to assess the condition of the state's coastal habitats using multiple measures of water quality, sediment quality, and biological condition. Sampling was subsequently expanded to include components required for the National Coastal Assessment (Coastal 2000) Program. Habitats are classified as either tidal creeks (<#60; 100 meters in width) or larger open water bodies. Approximately 30 sites are sampled within each habitat during the summer months using a probability-based random sampling design. Results obtained from the first two years of sampling documented significant differences in several water quality parameters (DO, salinity, pH, turbidity, fecal coliform bacteria, total nitrogen, TKN, total phosphorus) and biological measures (chlorophyll-a, finfish and crustacean abundance and biomass and a number of benthic species) between the tidal creek and open water habitats. These differences highlight the value of partitioning shallow water habitats separately from the larger open water bodies traditionally sampled in estuarine monitoring programs, especially since tidal creeks serve as critical nursery areas for many species. Based on the differences observed, there is a clear need to identify different physical and biological thresholds for evaluating the condition of each habitat type.  相似文献   

3.
The mid-Atlantic region of the United States has a wide diversity of natural resources. Human pressures on these natural resources are intense. These factors have resulted in the collection of substantial amounts of environmental information about the region by EPA (both Regional and Research Offices), other governmental agencies, industry, and environmental groups. EPA Regional Offices comprehend first hand the importance of environmental data and are extremely supportive of investments in these data. Environmental data are used prominently in a variety of strategic planning and resource management initiatives. In EPA Region 3, the use of scientifically-sound environmental data is, in fact, one of our strategic programmatic goals. Environmental information is captured and assessed continuously by Regional staff, sometimes working in partnership with other Federal and State agencies, to derive relevant resource management conclusions. The restoration goals for the Chesapeake Bay are based on environmental indicators and resulting data. Attainment of the water quality objectives for streams and coastal estuaries are predicted on monitoring data. Our initiative in the Mid-Atlantic Highlands area uses environmental indicators to measure the condition of forests and streams. Landscape-level indicators will provide unique opportunities for the use of data in planning and management activities in support of the principles of community-based activism and sustainable development. Significant value is added to these data during their use by Regional managers. Regional programs, such as the Chesapeake Bay Program and several National Estuary Programs, are founded in environmental data. Environmental information is used by the Regional program managers to ascertain whether programs are accomplishing their intended objectives. Finally, Regional programs provide a crucial means for disseminating this information to broad segments of the public, so that a better informed and educated client base for effective environmental protection will develop.  相似文献   

4.
Dissolved Oxygen Conditions in Northern Gulf of Mexico Estuaries   总被引:6,自引:0,他引:6  
Because deficient dissolved oxygen (DO) levels may have severe detrimental effects on estuarine and marine life, DO has been widely used as an indicator of ecological conditions by environmental monitoring programs. The U.S. EPA's Environmental Monitoring and Assessment Program for Estuaries (EMAP-E) monitored DO conditions in the estuaries of the Gulf of Mexico from 1991 to 1994. DO was measured in two ways: 1) instantaneous profiles from the surface to the bottom were taken during the day, and 2) continuous measurements were taken near the bottom at 15 min intervals for at least 12 h. This information was summarized to assess the spatial distribution and severity of DO conditions in these estuaries. Depending on the criteria used to define hypoxia (DO concentrations usually <2 mg L-1 or <5 mg L-1) and the method by which DO is measured, we estimate that between 5.2 and 29.3% of the total estuarine area in the Louisianian Province was affected by low DO conditions.  相似文献   

5.
In the early 1990s, EPA's Environmental Monitoring and Assessment Program (EMAP) documented the ecological condition of the overall population of small estuaries along the mid-Atlantic coast of the United States. However, the Program did not provide detailed information on the condition of individual estuaries less than 260 km2 in surface area, a group of estuaries of concern to environmental managers. To address the needs of environmental managers, when EMAP returned to the region in summer 1997, it included a study of the spatial variability of ecological indicators within individual small estuaries. At 127 probability-based sites in 10 estuaries, EMAP measured a variety of parameters of water quality and sediments, including dissolved oxygen (DO), nutrients, grain size of sediments, contaminants in sediments, and community structures of benthic macroinvertebrates. From this information the ecological condition (e.g., percent area with DO concentrations below 5mg L–1) for each estuary, along with 90% confidence interval, was determined. The width of the confidence interval was then recalculated for sample sizes ranging from two stations to the total number of stations sampled in that estuary. Confidence interval widths were then plotted against sample size. These plots can be useful in designing future regional monitoring programs with a goal of describing conditions in individual systems as well as broad geographic regions. Results illustrate that beyond five stations per estuary, the reduction in the width of the confidence interval with increasing sampling intensity is relatively small; however, individual program managers need to determine "how small is small enough."  相似文献   

6.
During June and July, 2002, forty-seven stations were sampled within estuaries along the gulf coast of the state of Veracruz, MX, using a probabilistic survey design and a common set of response indicators. The objective of the study was to collect information to assess the condition of estuarine waters within the state of Veracruz, and to provide data that would strengthen future assessments of Gulf of Mexico estuaries. Samples for water quality, sediment contaminants, sediment toxicity, and benthic populations were collected in a manner consistent with EPA’s National Coastal Assessment (NCA). Data were evaluated by comparing indicator measurements to tropical waters threshold values cited in US EPA’s National Coastal Condition Report II, 2004, for tropical waters. In Veracruz, 75% of the area sampled rated poor for water quality, attributed primarily to high concentrations reported for chlorophyll a, and dissolved nutrients. One percent of the area exhibited poor sediment quality, based on PAH and metals concentrations. Compared to US estuaries of the Gulf of Mexico, water quality observed in Veracruz estuaries was more affected by nutrient over-enrichment. The probabilitistic nature of the survey design allowed for the comparison of the condition of Veracruz and the US GOM estuaries.  相似文献   

7.
Federal and state environmental agencies conduct several programs to characterize the environmental condition of Chesapeake Bay. These programs use different benthic indices and survey designs, and have produced assessments that differ in the estimate of the extent of benthic community degradation in Chesapeake Bay. Provided that the survey designs are unbiased, differences may exist in the ability of these indices to identify environmental degradation. In this study we compared the results of three indices calculated on the same data, and the assessments of two programs: the Chesapeake Bay Program and the Mid-Atlantic Integrated Assessment (MAIA). We examined the level of agreement of index results using site-based measures of agreement, evaluated sampling designs and statistical estimation methods, and tested for significant differences in assessments. Comparison of ratings of individual sites was done within separate categories of water and sediment quality to identify which indices summarize best pollution problems in Chesapeake Bay. The use of different benthic indices by these programs produced assessments that differed significantly in the estimate of degradation. A larger fraction of poor sites was classified as good by the Environmental Monitoring and Assessment Program’s Virginian Province and MAIA benthic indices compared to the Chesapeake Bay benthic index of biotic integrity, although overall classification efficiencies were similar for all indices. Differences in survey design also contributed to differences in assessments. The relative difference between the indices remained the same when they were applied to an independent dataset, suggesting that the indices can be calibrated to produce consistent results.  相似文献   

8.
通过对美国环境实验室认定现用标准(2003 NELAC Standard)的研究,介绍了美国现行使用的环境实验室认定过程中能力验证、实地评估、认定程序、质量体系和认证机构认可5个部分的方法、程序、评定模式、组织管理等内容,对我国开展环境监测实验室的资质认定工作具有一定的借鉴作用.  相似文献   

9.
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 provides Chesapeake Bay monitoring programs with a uniform tool with which to characterize bay-wide benthic community condition and assess the health of the Bay. A probability-based design permits unbiased annual estimates of areal degradation within the Chesapeake Bay and its tributaries with quantifiable precision. However, of greatest interest to managers is the identification of problem areas most in need of restoration. Here we apply the B-IBI to benthic data collected in the Bay since 1994 to assess benthic community degradation by Chesapeake Bay Program segment and water depth. We used a new B-IBI classification system that improves the reliability of the estimates of degradation. Estimates were produced for 67 Chesapeake Bay Program segments. Greatest degradation was found in areas that are known to experience hypoxia or show toxic contamination, such as the mesohaline portion of the Potomac River, the Patapsco River, and the Maryland mainstem. Logistic regression models revealed increased probability of degraded benthos with depth for the lower Potomac River, Patapsco River, Nanticoke River, lower York River, and the Maryland mainstem. Our assessment of degradation by segment and water depth provided greater resolution of relative condition than previously available, and helped define the extent of degradation in Chesapeake Bay.  相似文献   

10.
11.
The Mobile Bay estuary in the northern Gulf of Mexico provides a rich habitat for many fish and shellfish, including those identified as economically and ecologically important. The National Estuary Program in Mobile Bay has focused on restoration of degraded estuarine habitat on which these species depend. To support this effort, we used statistical techniques of ordination, cluster analysis, and discriminant analysis to relate distributions of individual fish and shellfish species and species assemblages to two dozen water quality and habitat variables in a geo-referenced database. Species appeared to respond to dominant gradients of low to high salinity and upland to offshore habitat area; many of the 15 communities identified via cluster analysis showed aggregated spatial distributions that could be related to habitat characteristics. Species in the Mobile River Delta were distinct from those in other areas of the estuary. This analysis supports habitat management in the Mobile Bay estuary; however, due to mobility of organisms among sampling locations and the dynamic environmental conditions in estuaries, we conclude that the analyses presented here are most appropriate for an evaluation of the estuary as a whole.  相似文献   

12.
Our environmental concerns prompt launching large monitoring programs. Examining the history and accomplishments of similar endeavors is the best way to avoid errors. One lesson taught by the oldest and largest survey of national renewable resources in the United States, the Forest Inventory and Analysis Program, is that the program itself is not capable of learning from its errors. Among other problems that beset big programs are unrealistic promises. It is not possible to inventory every animal and plant species in the United States and their habitats as the newly created National Biological Survey vows to do. Even if it were possible, this would hardly help to attain the ultimate goal of the Survey, survival of all species. In his request to fund the Survey, Secretary of the Interior, Bruce Babbitt, compared the conflict between economic development and environmental integrity with train wrecks. This metaphor is as brilliant as it is deceitful. Its brilliance, attested by the success with the press and legislature, is in a vivid and blithe image suggesting that, given sufficient information, the conflict could be averted. After all, railroad accidents are rare and avoidable exceptions. This hopeful situation cannot be honestly compared with the plight of our environment. The crucial piece of information — that there is no spare track for economic development — is readily available. Our population and economic growth take place in the same space that has already been fully occupied by other species. To be trustworthy, monitoring programs should face the reality that development necessitates environmental degradation.  相似文献   

13.
We developed a systematic process to evaluate state/tribal bioassessment programs to provide information about the rigor of the technical approach. This is accomplished via on-site interviews to produce an evaluation that assigns one of four levels of rigor as an outcome. Level 4 is the most rigorous and reflects a technical capacity to accurately determine incremental condition and support management programs. The remaining three levels are less able to assess incremental condition and are appropriate for only some management support needs. Accurately determining impairment and diagnosing pollution-specific stressors are fundamental tasks that states/tribes must accomplish to provide management support. This goal is fulfilled to varying degrees by most states/tribes. The evaluation employs a checklist and a sliding scale of rigor for 13 technical elements. Feedback is provided to each state/tribe via a technical memorandum that describes the technical components of the monitoring program, highlights strengths, and recommends improvements for specific technical issues. This can be used to refine the bioassessment and monitoring programs to better support management programs. The results of 14 state/tribal evaluations are included here. The majority (nine states, one tribe) revealed that most operate at level 2 with developmental activities that will elevate the level of program rigor already underway. Two states operate level 4 programs and each have numeric biocriteria and refined designated uses in their water quality standards. This is the ultimate goal of the process of engaging states in the development of bioassessment programs in the U.S.  相似文献   

14.
The U.S. Environmental Protection Agency (EPA) is working with federal, state, local, and non-governmental partners to produce an interactive, spatial inventory of environmental data in the mid-Atlantic region. The inventory will include maps of sampling locations, lists of measurements, and design information for hundreds of research sites and monitoring programs. It will also feature user-defined queries, resulting in customized maps that satisfy search criteria. (For example, "Display the probability-based surveys that measure dry deposition and nutrient availability in soils"). The inventory will be used in an interagency pilot study, instigated by the National Science and Technology Council's Committee on the Environment and Natural Resources, to integrate environmental monitoring and research activities. The inventory will also provide information for a regional ecological assessment led by EPA Region 3 and the Office of Research and Development. In addition, an interagency consortium will use the inventory to identify suitable field data for assessing the accuracy of satellite imagery. In each of these three applications, the inventory will be tested and evaluated as a potential prototype for completing additional regions of the U.S. Maintained as an Oracle database, the inventory is accessible on the internet at http://www.epa.gov/monitor/. Currently, ten inventory records are on-line for demonstration. The complete federal inventory of approximately 180 records will be accessible on-line by October, 1997; approximately 200 state, local and non-governmental records are scheduled for on-line access by April, 1998.  相似文献   

15.
The design of environmental monitoring programs is frequently hampered by a lack of objective, quantitative criteria for evaluating alternative monitoring variables. In this paper we describe two such criteria, which we call samples required — the number of samples required to detect a given change in value — and information imparted — the amount of environmental information revealed by the monitoring variable. We then use these criteria to evaluate fin erosion in winter flounder (Pleuronectes americanus) and Dover sole (Microstomus pacificus) as marine environmental monitoring variables. Two methods for determining the samples required use contaminated and reference areas to estimate the sample statistics of a hypothetical impacted population. The first method is based on the overall difference in the proportions of diseased fish in the reference and hypothetical populations. The second treats the proportion of diseased fish in individual trawls as the variate and determines the samples required based on the mean and variance of the reference and contaminated populations. We use both methods to predict the number of trawls needed to detect an increase of 200% in fin erosion in the reference population. The first method had greater statistical power but assumes spatially homogeneous populations. The second method accounts for environmental patchiness. For Dover sole it predicted 1661 trawls would be needed to detect the 200% increase. An estuarine winter flounder population would require 74 trawls, and an oceanic winter flounder population would require 142.5 trawls. It appears that fin erosion in winter flounder may be a useful indicator of environmental contamination, but several stipulations apply. Migration may inflate the number of diseased fish observed in the reference population, and a more detailed etiology of the disease is required, including an understanding of what contaminants are responsible for manifestation of the disease.  相似文献   

16.
A benthic index for northern Gulf of Mexico estuaries has been developed and successfully validated by the Environmental Monitoring and Assessment Program for Estuaries (EMAP-E) in the Louisianian Province. The benthic index is a useful and valid indicator of estuarine condition that is intended to provide environmental managers with a simple tool for assessing the ecological condition of benthic macroinvertebrate communities. Associations between the benthic index and indicators of hypoxia, sediment contamination, and sediment toxicity were investigated to determine the most probable cause(s) of degraded benthic condition. The results showed that, on a local scale, the associations between the benthic index and potential environmental causes differed among estuaries. In Pensacola Bay, FL, for example, there was a significant association between the levels of toxic chemicals (e.g. DDT, silver, and TBT) in the sediment and the benthic index, especially in the bayous which have known sediment contamination problems. In Mobile Bay, however, degraded benthic communities were more closely associated with eutrophication and hypoxia. Nevertheless, a benthic index is a valuable tool for identifying areas that could be already degraded and tracking the status of environmental condition in large geographical regions.  相似文献   

17.
The combined effects of human activities and natural variability present significant challenges to the goals of protecting, restoring, and sustaining coastal ecosystems. Meeting these challenges and resolving conflicts in an informed fashion will require: (1) more timely detection and prediction of environmental changes and their consequences; and (2) more timely access to relevant environmental information. The achievement of these goals depends on the development of a sustained and integrated coastal ocean observing system (ICOOS) that insures timely access to the data and information required to improve: (1) climate predictions and the effects of changes in the weather on coastal populations; (2) efforts to sustain and restore healthy coastal marine ecosystems and living marine resources; and (3) compliance monitoring and evaluations of the efficacy of environmental policies. Although the responsible federal and state agencies all require similar environmental information, many separate programs have evolved for collecting, managing, and analyzing data for various purposes. Consequently, there is too much redundancy; access to diverse data from disparate sources is limited and time consuming; and individual programs are inevitably underfunded and too limited in scope. A system is needed that coordinates and integrates many of the elements of these programs to minimize redundancy, be more comprehensive, provide more timely access to data and information, and satisfy the information needs of a greater number of user groups in a more cost-effective fashion. This is the purpose of the ICOOS.  相似文献   

18.
Evaluating the impacts of point source discharges on fish species in estuarine environments can be challenging because of a paucity of resident species. We evaluated the biology of rock gunnel (Pholis gunnellus) at three relatively uncontaminated sites in the Bay of Fundy, along the Atlantic coast of Canada. Rock gunnel are seasonally resident (April to November) in tide pools, but little was known about their life history in Atlantic Canada or their potential for use for monitoring environmental quality. Fish were collected between April and November, and ranged from 2.46 g--15.2~g in weight and 97 mm-170 mm in length, with a maximum age of 7 years. Both males and females were similar in size, and both reached sexual maturity at a size of 5.5 g. Organ weights and condition indices of fish were stable from spring when they returned from offshore (April to May) until late summer (August to September), but fall fish (October to November) had slightly larger gonads, livers and condition indices. Rock gunnel may be a useful indicator to provide insight into local impacts of point sources over a short time period. However, they do not provide adequate information on reproductive development and performance since they are not exposed to onshore contaminants during the periods of gonadal development that have most commonly found to be sensitive to anthropogenic stressors.  相似文献   

19.
The goals of environmental legislation and associated regulations are to protect public health, natural resources, and ecosystems. In this context, monitoring programs should provide timely and relevant information so that the regulatory community can implement legislation in a cost-effective and efficient manner. The Safe Drinking Water Act (SDWA) of 1974 attempts to ensure that public water systems (PWSs) supply safe water to its consumers. As is the case with many other federal environmental statutes, SDWA monitoring has been implemented in relatively uniform fashion across the USA. In this three part series, spatial and temporal patterns in water quality data are utilized to develop, compare, and evaluate the economic performance of alternative place-based monitoring approaches to current monitoring practice. Under the Safe Drinking Water Act (SDWA), a common list of over 90 contaminants is analyzed nationwide using EPA-authorized laboratory procedures. National and state-level summaries of SDWA data have shown that not all contaminants occur in all places at all times. This hypothesis is confirmed and extended by showing that only a few (less than seven) contaminants are of concern in any one of 19 Iowa surface water systems studied. These systems collectively serve about 350,000 people and their sizes vary between 1,200 and 120,000. The distributions of contaminants found in these systems are positively skewed, with many non-detect measurements. A screening strategy to identify such contaminants in individual systems is presented. These findings have significant implications not only for the design of alternative monitoring programs, but also in multi-billion-dollar decisions that influence the course of future drinking water infrastructure, repair, and maintenance investments.  相似文献   

20.
In recent years, several monitoring programs have been established as a consequence of EU Directives which include requirements for monitoring the quality of water resources (drinking water, groundwater and surface water). Plant protection products (PPPs) are an obvious target for monitoring activities, since they are directly released into the environment. In Italy, the National Environmental Protection Agency (ISPRA ex APAT) has recently published two reports containing the results of the National Plans for Control of Environmental Effects of PPP. These documents contain the collection of monitoring data related to the presence of PPP residues in surface water and groundwater. The first objective of this work was to critically analyze the results of monitoring campaigns on pesticide residues in surface waters in Italy. In particular, the paper focuses on whether and how the Italian approach satisfies the requirements of the Water Framework Directive, whether they are representative of the whole national territory, and how the utilized approach is appropriate for the characterization of risk to surface water. Starting from this analysis, some considerations about the limits of environmental monitoring as a tool for managing risk were highlighted.  相似文献   

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