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91.
There is considerable concern about the effects of contaminants on organisms at higher trophic levels, as well as interest in developing bioindicators of ecological health. In this article we examine the levels of arsenic, cadmium, chromium, lead, manganese, mercury, and selenium in the gonads, liver and muscle of Florida gar (Lepisosteus platyrhincus) from Lake Okeechobee in south-central Florida. Gar are top-level predators in freshwater ecosystems. We expected that there would be differences in metal levels as a function of tissue, and predicted differences as a function of sex, size, and location around the lake. There were significant differences among tissues for all metals, but there were few differences as a function of size and gender, which may relate to the generally low levels of metals. Mercury levels were significantly higher in gar collected from the north, and arsenic levels were significantly higher in the gar collected from the south. All metal levels in the muscle of gar collected from Lake Okeechobee were similar to, or lower than those generally reported from other areas of the United States. Thus, although the levels of mercury from the Everglades to the south of Lake Okeechobee are sufficiently high to result in human fish consumption advisories, there are none for Lake Okeechobee. The mercury levels in fish muscle from Lake Okeechobee are lower than from many waters in the U.S. and do not pose a problem for humans. However, liver levels average over the 0.5 microg g(-1) level considered safe for human consumption, and might pose a problem for non-human consumers that eat the fish whole.  相似文献   
92.
This article presents a database developed to determine the potential reuse of contaminated sites for primarily ecologically and culturally based activities. The database consists of 172 quantitative and qualitative measures of on‐site land suitability, ecological, cultural, and recreational value, and off‐site suitability, economic, and demographic information. Using sites owned by the U.S. Department of Energy (DOE) as a case study, the article evaluates the quality of available data and suggests ways of using it for planning ecologically sensitive remediation activities and future land use. This type of database can be developed and used by anyone who needs to select, review, or evaluate site remediation and future land use options. Also discussed are the challenges associated with compiling and using data that has been generated by many sources over several years. © 2003 Wiley Periodicals, Inc.  相似文献   
93.
As the United States and other countries move toward a greater reliance on nuclear energy, it becomes increasingly important to characterize the environment around such facilities to protect society, human health, and the environment. This article presents an ecological, multidisciplinary approach to gathering the information needed to establish baselines, site new nuclear facilities, protect existing nuclear facilities and nuclear wastes, improve the basis for emergency planning, devise suitable monitoring schemes to ensure continued protection, provide data to track local and regional response changes, and provide for mitigation, remediation, and decommissioning planning. We suggest that there are five categories of information or data needs: (1) geophysical, sources, fate and transport; (2) biological systems; (3) human health; (4) stakeholder and environmental justice; and (5) societal, economic, and political. All of these categories are influenced by temporal and spatial patterns, vulnerabilities, and global changes. These informational needs are more expansive than the traditional site characterization but encompass a suite of physical, biological, and societal needs to protect all aspects of human health and the environment, not just physical health. We suggest that technical teams be established for each of the major informational categories, with appropriate representation among teams and with a broad involvement of a range of governmental personnel, natural and social scientists, Native Americans, environmental justice communities, and other stakeholders. Although designed for nuclear facilities, the templates and information teams can be adapted for other hazardous facilities. © 2013 Wiley Periodicals, Inc.  相似文献   
94.
Although most insects are vulnerable to predation by a variety of predators, including birds, there are few direct observational studies in the wild of avian predation on adult butterflies. We examined the predatory behavior of smooth-billed anis (Crotophaga ani) on butterflies, and the spacing behavior of the butterflies which were concentrated on a mineral-rich beach on the Cristalino River, in Mato Grosso, Brazil. We studied eight of the most regularly occurring butterfly species which came each morning to engage in "puddling." Most species of butterfly were closely associated with conspecifics, although nearest-neighbor distance varied among species. The pierids - "yellows" (Aphrissa statira, Phoebis trite), "oranges" (Phoebis argante), and sometimes "whites" (Daptoneura leucadia) - formed very dense groups (or clusters) of up to 1,000 individuals occasionally joined by a few kite swallowtails (Eurytides spp.). Most other butterfly species formed small groups (e.g., daggerwings, Marpesia spp.) or were dispersed individually and non-clumped over the beach (e.g., dingy purplewing, Eunica monima). Anis foraged using two strategies: rapid frontal attack on dense groups of butterflies (yellows, oranges, whites), and a stealthy approach to solitary butterflies (mainly purplewings) or those in small groups. For yellows, the most common butterfly caught by anis, the capture rate reached over 6 per 15 min per ani, and about 8% of those captured managed to escape. Capture rates were much lower for the other species. Time of day, age of the ani (adult or young-of-the-year), and total number of each butterfly species present accounted for variation in the number of each species captured by anis. The number of butterflies captured per 15 min increased as the number of butterflies present increased, but reached a threshold beyond which the capture rate did not increase. The capture rate per individual butterfly (individual risk) decreased with group size up to a group of 40 individuals and remained low with further increases. Thus a butterfly in a group of 100 was no less likely to be eaten than one in a group of 40. For individual ani forays into dense groups of pierids, an individual ani was unable to catch more than 16, regardless of group size. These data confirm the dilution effect of group size for butterflies; each individual yellow or orange was less at risk from ani predation when in a group.  相似文献   
95.
Mercury bioaccumulation in organisms from three Puerto Rican estuaries   总被引:1,自引:0,他引:1  
We analyzed mercury levels in shrimp (Palaemonetes sp.), Blue Crabs (Callinectes sp.), fish (Tarpon Megalops atlantica and Tilapia Tilapia mossambica), lizards (Ameiva exsul), Cattle Egret (Bubulcus ibis) and Moorhen (Gallinula chloropus) in three estuaries in Puerto Rico in 1988. There were no quantifiable concentrations greater than the method detection limit of mercury in shrimp, crabs and lizards from any site. Mercury levels were also below detection limits in Tilapia, except for specimens collected at Frontera Creek, allegedly contaminated with mercury. However, mercury levels ranged from 92–238 g/kg (wet weight) in Tarpon, a predaceous fish that feeds on smaller fish. Few of the birds had detectable levels of mercury. Our results indicate relatively low concentrations of mercury in biota collected in all of the three estuaries at most trophic levels, although 10 of 12 Tarpon fillet samples from Frontera had detectable mercury compared to 3 of 12 fillet samples for the other two lagoons.This project was partially funded by an EPA consent decree (Dynamac, Inc.) and NIEHS grant (ESO 5022) to EOSHI.  相似文献   
96.
Many federal, state, and private agencies deal with long‐term environmental problems within a transition framework where political administrations, funds, regulators, regulatory requirements, environmental conditions, and tribal and stakeholder concerns change. In this article, we examine the types of transitions, as well as important stabilities, that agencies face, the interactions with stakeholders that are vulnerable to disruption or failure, and some of the problems that develop as a result of these conditions, using the U.S. Department of Energy (US DOE's) Office of Environmental Management (EM) as a case study. Transitions, or instabilities, include changes in administrations at the federal, state, and local level; public perceptions and concerns; political climate; available funds; environmental conditions (e.g., global climate change, global contaminant transport, local and regional contamination); international and national business conditions; and site conditions (physical, chemical, biological). Governmental agencies operate under several different kinds of uncertainties, including scientific, fiscal‐year economic, technological, and societal. Not all information can be known, and the outcomes from scientific issues or technologies cannot always be predicted. The authors believe that transitions from one set of conditions to another can be more effectively integrated with the long‐term stability of environmental laws and regulations, and with the stability of the treaty rights and concerns of tribal nations, as well as the shorter‐term stability of career personnel and established programs. A sense of stability for government agencies allowing maintenance of ongoing environmental management programs can also be achieved through processes and programs, such as establishing long‐term contracts (for remediation or restoration work), schedule and scope documents, future land‐use documents, National Environmental Research Parks (which obligate lands to study and conservation), and other programs that set the direction of work and activities for many years. Further, two other factors are essential for success within any agency facing transitions: (1) expectations should be both forward‐looking and realistic, and (2) there must be flexibility in both programs and processes. The authors conclude that several features are essential to addressing some of the problems created by transitions, including information, integration, iteration, interaction, and inclusion. © 2009 Wiley Periodicals, Inc.  相似文献   
97.
Environmental managers are faced with the wise management, sustainability, and stewardship of their land for natural resource values. This task requires the integration of ecological evaluation with economics. Using the Department of Energy (DOE) as a case study, we examine the why, who, what, where, when, and how questions about assessment and natural resource protection of buffer lands. We suggest that managers evaluate natural resources for a variety of reasons that revolve around land use, remediation/restoration, protection of natural environments, and natural resource damage assessment (NRDA). While DOE is the manager of its lands, and thus its natural resources, a range of natural resource trustees and public officials have co-responsibility. We distinguish four types of natural resource evaluations: (1) the resources themselves (to the ecosystem), (2) the value of specific resources to people (e.g. hunting/fishing/bird-watching/herbal medicines), (3) the value of ecological resources to services for communities (e.g. clean air/water), and (4) the value of the intact ecosystems (e.g. forests or estuaries). Resource evaluations should occur initially to provide information about the status of those resources, and continued evaluation is required to provide trends data. Additional natural resource evaluation is required before, during and immediately following changes in land use, and remediation or restoration. Afterwards, additional monitoring and evaluations are required to evaluate the effects of the land use change or the efficacy of remediation/restoration. There are a wide range of economic methods available to evaluate natural resources, but the methods chosen depend upon the nature of the resource being evaluated, the purpose of the evaluation, and the needs of the agencies, natural resource trustees, public officials, and the public. We discuss the uses, and the advantages and disadvantages of different evaluation methods for natural resources.  相似文献   
98.
We compared levels of eight heavy metals in common tern eggs collected in 1982 (n=24) from coastal New Jersey with archived specimens collected from the same colonies in 1971 (N=9). Levels of all metals, except cobalt, showed a significant decrease over the 11 year period, with lead and nickel showing the greatest decline. Mercury levels declined over 50% based on geometric means. Cadmium and mercury showed the lowest levels in both years. Pair-wise correlation coefficients on log-transformed data revealed lower correlations in 1971, whereas most metal pairs showed significant correlations in 1982. Mercury levels showed significant positive correlations with cobalt, cadmium, and nickel in 1971, but were not correlated with levels of any other metal in 1982.  相似文献   
99.
US Federal law mandates that mined land be returned by mine operators to a condition capable of supporting its pre-mining use or a higher use. Previously forested lands have commonly been reclaimed to hayland/pasture or wildlife habitat, and most of these lands have been abandoned from management and rendered non-productive. This situation has left landowners in the position of converting these reclaimed mined lands to forests at a later date, if they choose to make them economically productive. Such land-use conversion, however, comes with a substantial up-front cost to the landowner, which makes the financial viability of such a conversion questionable. We examine the financial viability of reforestation of these previously reclaimed mine lands by calculating land expectation value (LEV) under a range of conditions that include forest type, site quality, and reforestation intensity. We find that conversion to white pine is viable on higher quality sites under low to moderate interest rates with low or high timber prices, but conversion to mixed hardwoods is only profitable under the high price scenario with low interest rates, and only on higher quality sites. We also consider the implications of a shift in reforestation burden from the landowner to the mine operator, and results suggest that including costs of reforestation as part of the mining operation creates a financially viable forest enterprise for landowners under all scenarios for both white pine and mixed hardwoods. Two forms of carbon payments that could encourage reforestation of previously reclaimed mined lands also are examined: an annual payment based upon the total accumulated carbon found on-site in a given year, and an annual payment based on only the increment of carbon storage each year. Our carbon payment results indicate that annual values of up to $5.17 per ton of carbon stored in hardwoods and $9.39 per ton of carbon stored in pines would be required to make reforestation profitable under the poorest conditions (high interest rates, low prices, and poor quality site) when the payment is based on accumulated on-site carbon, although lower values are required under more favorable scenarios. Payments that are based upon the annual increment of carbon must fall in the range of $8.66–$71.88 per ton of carbon stored in hardwoods and $0–$83.29 per ton of carbon stored in pines to make reforestation financially viable.  相似文献   
100.
Information on the spatial distribution and speciation of metals in nonhyperaccumulator plants is lacking. This study used synchrotron X-ray fluorescence (SXRF) compositional imaging to investigate the spatial distribution of Ni, Mn, Cu, Zn, and Fe in annual rings of black willow (Salix nigra L.) collected from a metal-contaminated area, and used X-ray absorption spectroscopy (XAS) to investigate Ni and Mn speciation in regions of the annual rings with elevated Ni concentrations. Annual rings were recollected in early 2003 from an individual known to be enriched with Ni from previous studies. Compositional imaging showed Ni and associated co-contaminants conservatively located in an annual ring. When compared with a corresponding photomicrograph, SXRF compositional images showed that metals were sharply constrained by the boundaries of the annual ring, indicating a sudden onset and cessation of uptake, and a lack of post-growth mobility of the metals. There was a particularly strong correlation between Ni and Mn in the metal-enriched annual ring (r = 0.8822), which suggested similar transport and binding behavior of these elements. X-ray absorption spectroscopy showed Ni and Mn to be present in the 2+ oxidation state. X-ray absorption near edge structure spectroscopy (XANES) fingerprinting of localized, highly Ni-enriched regions within the lumen of willow xylem vessels found similarities with Ni-pectic acid complexes, Ni-histidine, and NiSO4.  相似文献   
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