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31.
/ 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   
32.
The objective of this study was to investigate the efficacy of panel solar cookers in reducing urease activity in full-fat soybeans (Glycine max). Changes in urease activity of soaked (SM), coarse-milled (CM) and whole dry (WM) full fat soybeans were investigated by roasting for 0, 30, 60, 90, 120, 150 and 180 min in multiple reflector panel solar cookers, in a 3 3 3 factorial experiment. Soaking soybeans for 14 h reduced (p<0.05) 1 1P < 0.05 means that the probability (p) of falsely concluding significant difference between values obtained after statistical analysis was less than 5% (0.05). urease activity by 9%, from 6.58 meqNH3/g DM to 5.98 meqNH3/g DM. After 180 min of solar roasting, urease activity levels had declined by 81%, 67% and 23% in soaked, milled and whole dry soybeans respectively. Full fat soybean urease activity can be reduced faster in soaked than in dry soybeans. Findings suggest that there is potential in using multiple reflector panel solar cookers to reduce urease activity in full fat soybeans.  相似文献   
33.
Social organization in deer: Implications for localized management   总被引:2,自引:0,他引:2  
Populations of white-tailed deer (Odocoileus virginianus) inhabiting many state and national parks and suburban areas have grown to the point that they conflict with human activities. Conflicts range from destruction of vegetation through browsing to public perception that diseases carried by deer pose threats to human health. Traditional modes of hunting to control populations are inappropriate in many of these areas because of intense human development and activity. This article explores an alternative approach for population reduction based on deer social organization. Female white-tailed deer are highly philopatric and female offspring remain near their dams for life. This suggests that a population expands slowly as a series of overlapping home ranges in a form analogous to the petals on a rose. Incorporating the rose petal concept into a model of population growth shows that removal of deer by family unit can potentially alleviate conflicts in localized areas for as many as 10–15 yr.  相似文献   
34.
Pathogens, ammonia, odor, and greenhouse gas emissions are serious environmental concerns associated with swine production. This study was conducted in two manure pits (33,000 L each) to determine the influence of 1.5 or 3.0 g thymol L(-1) and 80 mg L(-1) urease inhibitor amendments on urea accumulation, coliform bacteria, odor, and methane emission. Each experiment lasted 18 or 19 d, during which time 30 to 36 250-mL samples (six per day) were withdrawn from underneath each pit and analyzed for urea, thymol, volatile fatty acids, coliform bacteria, and Campylobacter. At the end of each experiment, six 50-g samples from each pit were placed in serum bottles, and gas volume and composition were determined periodically for 28 d. Compared with the control pit, volatile fatty acids production was reduced 64 and 100% for the thymol amendments of 1.5 and 3.0 g L(-1), respectively. Viable coliform cells were reduced 4.68 and 5.88 log10 colony-forming units kg(-1) of slurry for the 1.5 and 3.0 g thymol L(-1), respectively, and Escherichia coli were reduced 4.67 and 5.01 log10 colony-forming units kg(-1) of slurry, respectively. Campylobacter was not detected in the pits treated with thymol, in contrast to 63% of the samples being positive for the untreated pit. Urea accumulated in the treated pits from Day 3 to 6. Total gas production from serum bottles was reduced 65 and 76% for thymol amendments of 1.5 and 3.0 g L(-1), respectively, and methane was reduced 78 and 93%, respectively. These results suggest that thymol markedly reduces pathogens, odor, and greenhouse gas emissions from a swine production facility. The urease inhibitor produced a temporary response in conserving urea.  相似文献   
35.
The increase in damage due to natural disasters is directly related to the number of people who live and work in hazardous areas and continuously accumulate assets. Therefore, land use planning authorities have to manage effectively the establishment and development of settlements in flood-prone areas in order to avoid the further increase of vulnerable assets. Germany faced major destruction during the flood in August 2002 in the Elbe and Danube catchments, and many changes have been suggested in the existing German water and planning regulations. This article presents some findings of a “Lessons Learned” study that was carried out in the aftermath of the flood and discusses the following topics: 1) the establishment of comprehensive hazard maps and flood protection concepts, 2) the harmonization of regulations of flood protection at the federal level, 3) the communication of the flood hazard and awareness strategies, and 4) how damage potential can be minimized through measures of area precaution such as resettlement and risk-adapted land use. Although attempts towards a coordinated and harmonized creation of flood hazard maps and concepts have been made, there is still no uniform strategy at all planning levels and for all states (Lae nder) of the Federal Republic of Germany. The development and communication of possible mitigation strategies for “unthinkable extreme events” beyond the common safety level of a 100-year flood are needed. In order to establish a sustainable and integrated flood risk management, interdisciplinary and catchment-based approaches are needed.  相似文献   
36.
Although the benefits of dam construction are numerous, particularly in the context of climate change and growing global demand for electricity, recent experience has shown that many dams have serious negative environmental, human, and political consequences. Despite an extensive literature documenting the benefits and costs of dams from a single disciplinary perspective, few studies have simultaneously evaluated the distribution of biophysical, socio-economic, and geopolitical implications of dams. To meet the simultaneous demands for water, energy, and environmental protection well into the future, a broader view of dams is needed. We thus propose a new tool for evaluating the relative costs and benefits of dam construction based on multi-objective planning techniques. The Integrative Dam Assessment Modeling (IDAM) tool is designed to integrate biophysical, socio-economic, and geopolitical perspectives into a single cost/benefit analysis of dam construction. Each of 27 different impacts of dam construction is evaluated both objectively (e.g., flood protection, as measured by RYI years) and subjectively (i.e., the valuation of said flood protection) by a team of decision-makers. By providing a visual representation of the various costs and benefits associated with two or more dams, the IDAM tool allows decision-makers to evaluate alternatives and to articulate priorities associated with a dam project, making the decision process about dams more informed and more transparent. For all of these reasons, we believe that the IDAM tool represents an important evolutionary step in dam evaluation.  相似文献   
37.
Traditional ecological knowledge (TEK) and the information and insights it offers to natural resource research and management have been given much attention in recent years. On the practical question of how TEK is accessed and used together with scientific knowledge, most work to date has examined documentation and methods of recording and disseminating information. Relatively little has been done regarding exchanges between scientific and traditional knowledge. This paper examines three workshop settings in which such exchanges were intended outcomes. The Barrow Symposium on Sea Ice, the Exxon Valdez Oil Spill Restoration Program Synthesis/Information Workshops, and the Alaska Beluga Whale Committee illuminate certain features of the preparation, format, and context of workshops or series of workshops and their eventual outcomes and influence. The examples show the importance of long-term relationships among participants and thorough preparation before the actual workshop. Further research should look more systematically at the factors that influence the success of a given workshop and the various ways in which participants perceive success.  相似文献   
38.
Soils adjacent to chromated copper arsenate (CCA)-treated fence posts along a fence line transecting different soil series, parent material, drainage classes, and slope were used to determine which soil properties had the most influence on As spatial distribution and speciation. Metal distribution was evaluated at macroscopic (total metal concentration contour maps) and microscopic scales (micro-synchrotron X-ray fluorescence maps), As speciation was determined using extended X-ray absorption fine structure spectroscopy, and redox status and a myriad of other basic soil properties were elucidated. All geochemical parameters measured point to a condition in which the mobilization of As becomes more favorable moving down the topographic gradient, likely resulting through competition (Meh-P, SOM), neutral or slightly basic pH, and redox conditions that are favorable for As mobilization (higher Fe(II) and total-Fe concentrations in water extracts). On the landscape scale, with hundreds of kilometers of fence, the arsenic loading into the soil can be substantial (~8-12 kg km). Although a significant amount of the As is stable, extended use of CCA-treated wood has resulted in elevated As concentrations in the local environment, increasing the risk of exposure and ecosystem perturbation. Therefore, a move toward arsenic-free alternatives in agricultural applications for which it is currently permitted should be considered.  相似文献   
39.
Analysis tools that combine large spatial and temporal scales are necessary for efficient management of wildlife species, such as the burrowing owl (Athene cunicularia). We assessed the ability of Ripley’s K-function analysis integrated into a geographic information system (GIS) to determine changes in burrowing owl nest clustering over two years at NASA Ames Research Center. Specifically, we used these tools to detect changes in spatial and temporal nest clustering before, during, and after conducting management by mowing to maintain low vegetation height at nest burrows. We found that the scale and timing of owl nest clustering matched the scale and timing of our conservation management actions over a short time frame. While this study could not determine a causal link between mowing and nest clustering, we did find that Ripley’s K and GIS were effective in detecting owl nest clustering and show promise for future conservation uses.  相似文献   
40.
ABSTRACT: Irrigation development in Saskatchewan was initiated as an instrument to bring forth regional stability through drought proofing and diversification in the agricultural sector. This development has been surrounded by controversies. Particularly, some critics questioning its economic value to the farmer. In this study, irrigation on a farm is compared as a growth alternative to the expansion of dryland farming. Under relatively conservative machine replacement policies, modest family withdrawals, government subsidized irrigation loans, and relatively favorable gross operating margins, irrigation can be a profitable undertaking in the South Saskatchewan River Basin.  相似文献   
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