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211.
Abstract: Concentrating tourism activities can be an effective way to closely manage high‐use parks and minimize the extent of the effects of visitors on plants and animals, although considerable investment in permanent tourism facilities may be required. On coral reefs, a variety of human‐related disturbances have been associated with elevated levels of coral disease, but the effects of reef‐based tourist facilities (e.g., permanent offshore visitor platforms) on coral health have not been assessed. In partnership with reef managers and the tourism industry, we tested the effectiveness of concentrating tourism activities as a strategy for managing tourism on coral reefs. We compared prevalence of brown band disease, white syndromes, black band disease, skeletal eroding band, and growth anomalies among reefs with and without permanent tourism platforms within the Great Barrier Reef Marine Park. Coral diseases were 15 times more prevalent at reefs with offshore tourism platforms than at nearby reefs without platforms. The maximum prevalence and maximum number of cases of each disease type were recorded at reefs with permanently moored tourism platforms. Diseases affected 10 coral genera from 7 families at reefs with platforms and 4 coral genera from 3 families at reefs without platforms. The greatest number of disease cases occurred within the spatially dominant acroporid corals, which exhibited 18‐fold greater disease prevalence at reefs with platforms than at reefs without platforms. Neither the percent cover of acroporids nor overall coral cover differed significantly between reefs with and without platforms, which suggests that neither factor was responsible for the elevated levels of disease. Identifying how tourism activities and platforms facilitate coral disease in marine parks will help ensure ongoing conservation of coral assemblages and tourism. 相似文献
212.
Mercury, a toxic metal known to have several deleterious affects on human health, has been one of the principal contaminants of concern in the Great Lakes basin. There are numerous anthropogenic sources of mercury to the Great Lakes area. Combustion of coal, smelting of non ferrous metals, and incineration of municipal and medical waste are major sources of mercury emissions in the region. In addition to North American anthropogenic emissions, global atmospheric emissions also significantly contribute to the deposition of mercury in the Great Lakes basin. Both the USA and Canada have agreed to reduce human exposure to mercury in the Great Lakes basin and have significantly curtailed mercury load to this region through individual and joint efforts. However, many important mercury sources, such as coal-fired power plants, still exist in the vicinity of the Great Lakes. More serious actions to drastically reduce mercury sources by employing alternative energy sources, restricting mercury trade and banning various mercury containing consumer products, such as dental amalgam are as essential as cleaning up the historical deposits of mercury in the basin. A strong political will and mass momentum are crucial for efficient mercury management. International cooperation is equally important. In the present paper, we have analyzed existing policies in respective jurisdictions to reduce mercury concentration in the Great Lakes environment. A brief review of the sources, occurrence in the Great Lakes, and the health effects of mercury is also included. 相似文献
213.
A method for assessing environmental risk: A case study of Green Bay,Lake Michigan,USA 总被引:4,自引:0,他引:4
Hallett J. Harris Robert B. Wenger Victoria A. Harris David S. Devault 《Environmental management》1994,18(2):295-306
The Science Advisory Board of the US Environmental Protection Agency has recommended that risk reduction strategies become
the centerpiece of environmental protection. The goal in developing such strategies is to identify opportunities for greatest
reduction of ecological risks. This is a perspective that is significantly more comprehensive than the traditional focus on
human health risks arising from environmental degradation. The identification of ecological risks upon which environmental
protection efforts should be focused requires an ecological risk assessment methodology that is based on anthropogenic stressors
affecting an ecosystem and a set of impaired use criteria. A methodology based on this concept is developed and discussed
in this article. The methodology requires that risk values be assigned to each ecosystem stressor-impaired use pair that reflect
the degree to which the given stressor contributes to ecosystem risk as measured by the given impaired use criterion. Once
these data are available, mathematical analyses based on concepts from fuzzy set theory are performed to obtain a ranking
of ecosystem stressors. The methodology has been tested by applying it to a case study involving Green Bay of Lake Michigan.
A workshop was held in which 11 persons with extensive knowledge of the Green Bay ecosystem determined risk values through
a group-consensus process. The analytical portion of the methodology was then used to rank the ecosystem risks (stressors)
from several perspectives, including prevention management and remediation management. The overall conclusion of the workshop
participants was that the fuzzy set decision model is a useful and effective methodology for differentiating environmental
risk. 相似文献
214.
Gail Krantzberg 《Environment, Development and Sustainability》2006,8(3):413-424
As part of the commitments made by the governments of Canada and the United States in the Great Lakes Water Quality Agreement, Remedial Action Plans (RAPs) are being developed and implemented at Great Lakes Areas of Concern. The Areas of Concern are specific places around the Great Lakes basin ecosystem where environmental quality is degraded to the point that certain beneficial uses (the ability of fish, wildlife and humans to thrive) are impaired. According to the United States and Canada Great Lakes Water Quality Agreement of 1987, the federal governments, in cooperation with state and provincial governments, are to ensure the public is consulted throughout the development and implementation of the RAPs. While not explicit in the Agreement, it is logical to posit that given the effort and investment in environmental improvements, community capacity to sustain the recovery of beneficial uses beyond the life of the RAP should be a product of the RAP. This report examines a case study to test the hypothesis that public ownership of the RAP process can result in the development of community capacity to sustain environmental recovery. The question is, were the principles of the RAP, 10 years after delisting, taken into account to ensure sustainability of growth along the waterfront and within the Town? To arrive at the answer it is important to explore the approach used in the Collingwood Harbour RAP process, and concepts and principles of sustainable cities and towns. This paper provides evidence that such principles are being applied in Collingwood and were nurtured during the development and implementation of the RAP. 相似文献
215.
216.
Assessing Risk in Operational Decisions Using Great Lakes Probabilistic Water Level Forecasts 总被引:1,自引:0,他引:1
/ A method adapted from the National Weather Service's Extended Streamflow Prediction technique is applied retrospectively to three Great Lakes case studies to show how risk assessment using probabilistic monthly water level forecasts could have contributed to the decision-mak-ing process. The first case study examines the 1985 International Joint Commission (IJC) decision to store water in Lake Superior to reduce high levels on the downstream lakes. Probabilistic forecasts are generated for Lake Superior and Lakes Michigan-Huron and used with riparian inundation value functions to assess the relative impacts of the IJC's decision on riparian interests for both lakes. The second case study evaluates the risk of flooding at Milwaukee, Wisconsin, and the need to implement flood-control projects if Lake Michigan levels were to continue to rise above the October 1986 record. The third case study quantifies the risks of impaired municipal water works operation during the 1964-1965 period of extreme low water levels on Lakes Huron, St. Clair, Erie, and Ontario. Further refinements and other potential applications of the probabilistic forecast technique are discussed.KEY WORDS: Great Lakes; Water levels; Forecasting; Risk; Decision making 相似文献
217.
Marc Bekoff 《Journal of Agricultural and Environmental Ethics》1997,10(3):269-296
In this essay I argue that the evolutionary and comparative study of nonhuman animal (hereafter animal) cognition in a wide
range of taxa by cognitive ethologists can readily inform discussions about animal protection and animal rights. However,
while it is clear that there is a link between animal cognitive abilities and animal pain and suffering, I agree with Jeremy
Bentham who claimed long ago the real question does not deal with whether individuals can think or reason but rather with
whether or not individuals can suffer. One of my major goals will be to make the case that the time has come to expand. The
Great Ape Project (GAP) to The Great Ape/Animal Project (GA/AP) and to take seriously the moral status and rights of all animals
by presupposing that all individuals should be admitted into the Community of Equals. I also argue that individuals count
and that it is essential to avoid being speciesist cognitivists; it really doesn't matter whether ‘dogs ape’ or whether ‘apes
dog’ when taking into account the worlds of different individual animals. Narrow-minded primatocentrism and speciesism must
be resisted in our studies of animal cognition and animal protection and rights. Line-drawing into ‘lower’ and ‘higher’ species
is a misleading speciesist practice that should be vigorously resisted because not only is line-drawing bad biology but also
because it can have disastrous consequences for how animals are viewed and treated. Speciesist line-drawing also ignores within
species individual differences.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
218.
Winter Quarters Bay (WQB) is a small embayment located adjacent to McMurdo Station, the largest researchbase in Antarctica. The bay is approximately 250 m wide andlong, with a maximum depth of 33 m. Historically, trashfrom the McMurdo Station was piled on the steep shoreline ofWQB, doused with fuel and ignited. That practice hasceased, and the adjacent land area has been regraded tocover the residual waste. The bottom of WQB remainslittered with drums, equipment, tanks, tires, cables, andother objects, especially the southeastern side of the baywhere dumping took place. Sediments are contaminated withPCBs, metals, and hydrocarbon fuels. The objectives of this study were to map the distributionof organic contaminants in WQB, assess the toxicity of WQB sediments using a simple microbial test, anddetermine correlations between toxicity and contaminantlevels. The study suggests that adverse ecological effectshave occurred from one or more of the contaminants found inWQB but the source of the toxic impacts to bay sedimentsremains unknown. Whole sediment toxicity was onlycorrelated with oil-equivalent while solvent extracts ofsediments were correlated with PAHs and oil-equivalent. Theauthors recommend that an integrated research plan bedeveloped that focuses on determining what additionalinformation is needed to make informed decisions on possibleremediation of WQB. 相似文献
219.
Neilson MA Painter DS Warren G Hites RA Basu I Weseloh DV Whittle DM Christie G Barbiero R Tuchman M Johannsson OE Nalepa TF Edsall TA Fleischer G Bronte C Smith SB Baumann PC 《Environmental monitoring and assessment》2003,88(1-3):103-117
The Great Lakes Water Quality Agreement stipulates that the Governments of Canada and the United States are responsible for restoring and maintaining the chemical, physical and biological integrity of the waters of the Great Lakes Basin Ecosystem. Due to varying mandates and areas of expertise, monitoring to assess progress towards this objective is conducted by a multitude of Canadian and U.S. federal and provincial/state agencies, in cooperation with academia and regional authorities. This paper highlights selected long-term monitoring programs and discusses a number of documented ecological changes that indicate the present state of the open and nearshore waters of the Great Lakes. 相似文献
220.
D.P. Ryckman D.V. Weseloh P. Hamr G.A. Fox B. Collins P.J. Ewins R.J. Norstrom 《Environmental monitoring and assessment》1998,53(1):169-195
The levels of organochlorine contaminants (OCs) in the eggs of double-crested cormorants (Phalacrocorax auritus) from the Canadian Great Lakes, Lake Nipigon and Lake-of-the-Woods were monitored between 1970 and 1995. PCBs and p,p-DDE were present at the highest concentrations. Significant declines in OC concentrations on the Great Lakes were observed over this period for Lake Ontario, Lake Superior, Georgian Bay and North Channel but not Lake Erie where levels remained relatively stable. In the early 1970s, the greatest OC levels were generally observed in cormorant eggs from nesting sites in Georgian Bay and North Channel of Lake Huron. Between 1984 and 1995 mirex and PCB levels were consistently highest in samples from Lakes Ontario and Erie, respectively. Similar levels of PCDDs and PCDFs were observed from all regions of the Canadian Great Lakes in 1989. In general, OC levels in cormorant eggs between 1984-95 were ranked as follows: Lake Erie>Lake Ontario Lake Superior>Lake Huron. In 1995, eggshell thickness in Canadian Great Lakes cormorants, ranged from 0.423 to 0.440 mm and was on average only 2.3% thinner than pre-DDT era values. Between 1988 and 1996, 31 cormorant chicks with bill defects were observed at 16 different colonies (21% of all colonies surveyed) in Lakes Ontario and Superior, Georgian Bay and North Channel, and the main body of Lake Huron. No bill deformities were observed at reference sites in northwestern Ontario (Lake Nipigon and Lake-of-the-Woods). For the period 1988-96, the prevalence of bill defects in cormorant chicks (0.0 to 2.8/10,000 chicks) did not differ significantly (P > 0.05) among most regions in the Canadian Great Lakes. Georgian Bay was the only region to show a significant decrease in the prevalence of bill defects between the periods 1979-87 and 1988-95. 相似文献