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941.
Barry D. Solomon 《Environmental management》1998,22(1):9-17
Dendroica kirtlandii ). This particular recovery program actually began before passage of the federal ESA, when biologists alerted the Michigan
Department of Natural Resources of the perilously low population of this bird, which only breeds under jack pine (Pinus banksiana) trees in Michigan. By the time an ESA Recovery Team was formed for this bird in 1975 (the first such team created under
the ESA), a legacy of consensus and interagency cooperation was well established. This has led to successful efforts at habitat
management and control of its nest parasite, the brown-headed cowbird (Molothrus ater). While the Kirtland's warbler is not yet recovered, its population is near an all-time high, and its recovery is possible
within the next decade. When (and if) this happens, it will be clearly attributable to this successful model of federalism
for natural resources management. 相似文献
942.
Industry Response to the Challenge of Sustainability: The Case of the Canadian Nonferrous Mining Sector 总被引:3,自引:0,他引:3
Luis E. Sánchez 《Environmental management》1998,22(4):521-531
/ The paper investigates how the Canadian nonferrous sector is tackling the challenge of sustainable development. Although there is no consensus as to what sustainable development means in practice for management in the sector, at least three dimensions must be taken into account: (1) metals are recyclable, the availability of this resource is not a concern for the foreseeable future; (2) the need to minimize environmental impacts of metals exploration, extraction, transformation, consumption, and recycling; and (3) production activities should not be socially or culturally disruptive. The nonferrous mining industry faces several environmental problems. Some of the most significant are acid mine drainage, sulfur emissions, recycling, and metals toxicity. The industry has developed a number of responses to address these specific concerns as well as other more general challenges. Six strategies are described and analyzed: (1) research and development, (2) an effort of consensus building among stakeholders known as the Whitehorse Mining Initiative, (3) international networking, (4) active involvement in the development of environmental management standards, (5) management reorganization and (6) voluntary agreements. The importance of external factors in the shaping of corporate environmental management practices is discussed, in particular the role of government. Progress has been achieved in three areas: (1) managerial practices and organization, (2) reducing the impacts of ongoing operations and (3) minimizing future liabilities, but two significant fields of conflict remain, namely mining in wilderness areas and projects on aboriginal lands.KEY WORDS: Canada; Environmental management; Minerals industry; Nonferrous metals; Sustainable development; Whitehorse Mining Initiative 相似文献
943.
Suburban Areas in Developing Countries and Their Relationship to Groundwater Pollution: A Case Study of Mar del Plata, Argentina 总被引:1,自引:0,他引:1
Hector E. Massone Daniel E. Martinez Jose L. Cionchi Emilia Bocanegra 《Environmental management》1998,22(2):245-254
2 were sampled in order to verify the impact of these problems on groundwater. All samples were analyzed for major ions, and
about 30 of them for fecal coliforms and heavy metals. Nineteen samples were selected for pesticide analyses. The average
nitrate content was 80 mg/liter, eight times the regional background value. Fecal coliforms were detected in 60% of the analyzed
samples. Zinc content and a high Cl−/HCO3
− ratio were observed in the surroundings of the solid waste disposal area. Moreover, lindane and heptachlor pesticides were
detected in ten samples. 相似文献
944.
/ A methodology to estimate the number of pump-out facilities and dump stations required to service human waste disposal for recreational power boating activities in Pennsylvania during the 1994 boating season is described. Study results suggest that a total of 39 additional pump-out stations and 13 dump stations may be required on seven major waterbodies: The Three Rivers Area, Lake Erie/Presque Isle Bay, Raystown Lake, the Susquehanna River, the Delaware River, Lake Wallenpaupack, and the Kinzua Reservoir. Suggestions for improving the methodology are provided. KEY WORDS: Human waste; Recreation; Power boating; Waste facilities; Waste disposal; Pennsylvania 相似文献
945.
Joseph N. Lekakis 《Environmental management》1998,22(1):1-8
/ Collaboration of countries with an aim to share fresh surface water resources promises to generate potential joint benefits. Unfortunately, existing agreements lack the perspective and capacity to produce any real action in efficient cross-border water allocation. When that problem is encountered by any two adjacent countries claiming riparian rights to the same watercourse, this paper suggests that apossible solution to be examined is a water market. This market requires the relevant countries to engage in a bargaining process as described in the theory of bilateral monopoly. The bargaining process should determine both the water quantity to be transferred and the price to be paid. However, there has to be a fair allocation of the joint benefits resulting from the transfer for a sustainable price solution. As an empirical illustration, the paper examines the case of river Nestos shared by Bulgaria and Greece in the southern Balkans. A net revenue function quadratic in water is specified and estimated using scarce data on three agricultural crops in Greece. Sensitivity analysis on the size and distribution of the net benefits is also performed.KEY WORDS: Bilateral agreements; Water markets; Efficient allocation 相似文献
946.
/ Tidal marshes have been actively restored in Connecticut for nearly 20 years, but evaluations of these projects are typically based solely on observations of vegetation change. A formerly impounded valley marsh at the Barn Island Wildlife Management Area is a notable exception; previous research at this site has also included assessments of primary productivity, macroinvertebrates, and use by fishes. To determine the effects of marsh restoration on higher trophic levels, we monitored bird use at five sites within the Barn Island complex, including both restoration and reference marshes. Use by summer bird populations within fixed plots was monitored over two years at all sites. Our principal focus was Impoundment One, a previously impounded valley marsh reopened to full tidal exchange in 1982. This restoration site supported a greater abundance of wetland birds than our other sites, indicating that it is at least equivalent to reference marshes within the same system for this ecological function. Moreover, the species richness of birds and their frequency of occurrence at Impoundment One was greater than at 11 other estuarine marshes in southeastern Connecticut surveyed in a related investigation. A second marsh, under restoration for approximately ten years, appears to be developing in a similar fashion. These results complement previous studies on vegetation, macroinvertebrates, and fish use in this system to show that, over time, the reintroduction of tidal flooding can effectively restore important ecological functions to previously impounded tidal marshes.KEY WORDS: Estuarine; Tidal marsh; Wetland birds; Restoration 相似文献
947.
Bradford R. Crain 《Environmental management》1998,22(3):471-481
L and width 2w, then by a selection of viewing window is meant a choice of w, with the intent being to search for optimal viewing windows, with the goal in mind of improving variances of estimators
of population density, reducing sampling effort, while maintaining the property of unbiasedness. The notions of increasing
window sensitivity (IWS) and decreasing window sensitivity (DWS) are introduced, and a method of deriving confidence intervals
is discussed. 相似文献
948.
The paper provides a review of available information on the impact of recreation and tourism on environments, particularly on vegetation and soil, in Australia, with an emphasis on forests. Efforts have been made to compare the current research and development situation in Australia with some overseas countries such as the United States and the United Kingdom. While many documents reveal that Australia has been experiencing an increasingly high level of recreation and tourism use in its environments, only limited studies of environmental impacts of recreation and tourism have been published. Compared with other developed countries, particularly the United Kingdom and the United States, Australia lags behind in undertaking research in this area. The results of these limited studies and some observations indicate that the most common recreational and tourist activities (such as bush walking, camping, horse-riding) can, if not well managed, adversely affect the values of Australian natural and semi-natural resources. Overall, they can affect the vegetation and other recreational sites physically and biologically. Physical effects include track formation, soil loss and/or compaction and an increase in fire frequency. Littering and water pollution are also seen as impacts associated with bush walking and camping. Biological effects include causing damage to vegetation, increasing risk of myrtle wilt disease and the spread of the soil pathogen,Phytophthora cinnamomi, as well as assisting weed dispersal. Based on the information reviewed, the authors suggest the following areas as priorities for future research into the environmental impact of recreation and tourism in Australia: determine the type of natural features that attract recreation use; determine the quantitative relationship between the impact and the level of recreation and tourism use for different activities within major vegetation habitats; ascertain site carrying capacity or environment thresholds for major vegetation habitats and recreation activities; and determine the impacts of recreation and tourism for major regions and major vegetation habitats where there have been considerable nature-based recreation and tourism activities.1998 Academic Press 相似文献
949.
Fish Community Structure as a Measure of Degradation and Rehabilitation of Riparian Systems in an Agricultural Drainage Basin 总被引:7,自引:0,他引:7
/ Assessing the health of ecological components of agroecosystems may be accomplished by examining changes in the drainage basin, which serves as an integrator of the agroecosystem landscape. In this study we examined fish communities in terms of an array of indicators of structure and related these to changes in riparian vegetation and agricultural practice. Evidence suggests management practices designed to foster healthier environments by, for example, reestablishing riparian vegetation were associated with positive impacts on the integrity of the fish community. At the same time, continued intensification of agricultural practices in parts of the drainage basin in recent years likely has had an off-setting influence in overall improvements in agroecosystem health. Assessments of changes in the structure of the fish associations provide the balance sheet by which the counteracting influences can be aggregated and assessed.KEY WORDS: Fish community structure; Riparian system; Agricultural drainage basin 相似文献
950.
Marc Hockings 《Environmental management》1998,22(3):337-345
/ An approach to evaluating the effectiveness of management of protected areas is proposed. This approach has been used in developing an evaluation strategy for the Fraser Island World Heritage Area in Australia. The main component of the strategy is built upon the desired outcomes specified in the management plan for the area and thus provides a basis for assessing the extent to which the plan's objectives are being achieved. A series of monitoring programs have been proposed to enable this assessment. Examples of monitoring programs developed as part of the evaluation strategy are presented. A second component of the strategy monitors the implementation of the management plan. A management information system has been developed to record and report on the extent to which the specific actions specified in the management plan have been implemented. The strategy is discussed in relation to seven objectives set for the evaluation program in its design phase.KEY WORDS: Planning; Evaluation; Monitoring; Management; Protected areas 相似文献