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51.
This document describes a basis for the establishment of marine sediment quality guidelines for regulatory applications. It outlines a geochemical basis for identifying potential anomalies in the presence of inorganic contaminants in marine sediments and a biological or ecotoxicological basis for determining concentrations unlikely to result in adverse biological effects. These approaches are discussed in an exploratory fashion. It is intended that both approaches could be combined in a manner that takes account of sedimentary nature and composition as a conceptual and practical approach to the establishment of guidelines for regulatory applications associated with the protection of the marine environment. 相似文献
52.
加拿大油气系统温室气体逃逸排放清单简述 总被引:2,自引:0,他引:2
油气系统温室气体逃逸排放是温室气体排放清单的重要组成部分。加拿大在清单中统一考虑了油气系统可能存在的温室气体排放源,因此清单中不仅包括了温室气体的逃逸排放(泄漏、排空),还考虑了能源燃烧中的气体排放,所考虑的温室气体种类既包括甲烷,也包括二氧化碳。采用的是政府间气候变化专门委员会(IPCC)第三层次方法(Tier3),即设备清单法、操作时间法和活动水平法三种计算方法,详细地将排放源分类进行估算。该国对数据的管理、质量控制和质量评估、不确定性分析以及在如何保证数据的持续性方面的作法都值得我们学习和借鉴。 相似文献
53.
Marshall Gysi 《Journal of the American Water Resources Association》1981,17(6):956-961
ABSTRACT: Calgary, the fastest growing city in Canada, is about to expand its urban water supply facilities in order to meet peak summer demands. Most of Calgary's residential water is sold by flat rate. The effect of this pricing policy on peak and average demands is discussed. The true marginal cost of peak capacity from the new expansion is calculated. The effect of a proposed metering program on capacity expansion requirements is computed. It is concluded that metering should preceed the next capacity expansion. 相似文献
54.
《Environmental Hazards》2013,12(2):63-75
Abstract Although Canadian flood management efforts have gained worldwide recognition, flood damages continue to increase. The current practice for preventing, responding to and recovering from floods in Canada is described by focusing attention on the 1997 Red River and 1996 Saguenay River floods. A set of cultures is identified that contribute to the trend of increasing flood damages. These include a culture of conflict, a culture of land development, a culture that impeded native people from easily implementing flood management programs, a culture of institutional fragmentation and a culture of dependency. These foster an inevitable cycle of increasing flood damages. The potential of recent proposals made by Emergency Preparedness Canada and the Insurance Bureau of Canada to address these cultures is assessed. While these documents represent significant progress, they continue to adopt an intermittent project rather an ongoing program perspective, fail to identify the need to adopt specific initiatives tailored for aboriginal communities, and ignore the need to enhance the operational capacity of relevant public and private participants. Addressing these requirements will further reduce future losses and vulnerability. 相似文献
55.
Robert D. Cairns 《Resources Policy》1982,8(1):59-64
The level of rents attributable to natural resource producers depends on the risk faced by those producers. This paper argues that estimates of risk in mining should control for characteristics of firms such as diversification and debt financing. The capital asset pricing model is applied to securities of three Canadian nickel mining firms over the period 1961–1974. It is concluded that the level of risk was not unusually high. 相似文献
56.
Many firms generate large amounts of carbon dioxide and other greenhouse gases when they burn fossil fuels in their production processes. In addition, production of raw materials and other inputs the firms procure for their operations also generates greenhouse gases indirectly. These direct and indirect greenhouse gas emissions occur in many sectors of our economies. In this paper, we first present sector-specific estimates for such greenhouse gas emissions. We then show that estimates for such sector-specific greenhouse gas emissions are often required for various types of corporate as well as public policy analyses in both domestic and international contexts. Measuring greenhouse gas emissions resulting from firms' multi-stage production processes in a multi-sector context is relevant for policies related to the Kyoto protocol, an international agreement to limit global greenhouse gas emissions. For example, since the protocol allows firms to engage in trading and offsetting of their greenhouse gas emissions across national borders, provided that emissions are correctly measured, the firms can take advantage of such trading schemes by placing their energy-intensive production facilities globally and strategically. We present several case studies which illustrate the importance of this and other aspects of greenhouse gas emissions in firms' environmental management. We also argue that our modeling and estimation methods based on input-output analyses are suitable for the types of research goals we have in this paper. Our methods are applied to data for Canada and Japan in a variety of environmental management circumstances. 相似文献
57.
58.
ABSTRACT: The geochemistry and nature of the flow of ground water not only control the supply potential but constitute clues to the whole geology of an area. A study has been made of the largest available assemblage of data from 161 wells for the Island of Montreal collected by the Geological Survey of Canada in 1951–53. Data indicated that the system is generally subartesian, flowing from the principal topographically high areas towards the shores of the Island. As the probable use is about 13% of the estimated recharge of 140 million liters per day, most wells could be supplied by local recharge. The study has confirmed the predominance of calcium bicarbonate ground water from the carbonate sequence. The waters appeared to be saturated with respect to CaCO3 in all but 10 wells. The presence of other types of waters suggests the effects of the igneous intrusions of the area, the post-glacial marine submergence and the upward movement of waters from deep sources through fault and other structural zones. Confirmation of the significant variations in chemical composition in some neighboring wells indicated the future need for repetitive sampling from specific horizons for chemical and isotopic analyses. 相似文献
59.
Behdin Nowrouzi Basem Gohar Behnam Nowrouzi-Kia Martyna Garbaczewska Olena Chapovalov Étienne Myette-Côté 《International journal of occupational safety and ergonomics》2016,22(3):360-366
Purpose. The purpose of this particular study was to test a newly created instrument in describing the facilitators and barriers to occupational health and safety in small and medium-sized enterprises (SMEs) in Ontario, Canada. Methods. A cross-sectional design was used to identify the occupational health and safety culture of SMEs in public and private sectors in Ontario. Results. A total of 153 questionnaires were completed. The majority of respondents were female (84%) with a mean age of 49.8 years (SD 10.6). Seventy-four percent were supervisors. Seventy percent of respondents were from the private sector while 30% derived from the public sector including healthcare, community services, and non-profit organizations. Further, conducting regular external safety inspections of the workplace was found to be statistically associated with a safe work environment 2.88 95% CI [1.57, 5.27]. Conclusions. Strategies and training opportunities that focus on how to adapt occupational health and safety legislation to the nature and diversity of SMEs are recommended. Furthermore, employers may use such information to improve safety in their SMEs, while researchers can hopefully use such evidence to develop interventions that are applicable to meeting the occupational health and safety needs of SMEs. 相似文献
60.
Globally, ecosystem structure and function have been degraded by the cumulative effects (CE) of multiple stressors. To maintain ecosystem resilience, there is an urgent need to better account for CE in management decision-making at various scales. Current laws and regulations are supported by a multitude of frameworks and strategies that vary in application and terminology use across management agencies and geopolitical boundaries. We synthesized management frameworks that accounted for CE in marine ecosystems at the regional and national levels across western North America (Canada, United States, Mexico) to identify similarities and shared challenges to successful implementation. We examined examples of solutions to the identified challenges (e.g., interagency and cross-border partnerships to overcome challenges of managing for ecologically relevant spatial scales). Management frameworks in general consisted of 3 phases: scoping and structuring the system; characterizing relationships; and evaluating management options. Challenges in the robust implementation of these phases included lack of interagency coordination, minimal incorporation of diverse perspectives, and data deficiencies. Cases that provided solutions to these challenges encouraged coordination at ecological rather than jurisdictional scales, enhanced involvement of stakeholders and Indigenous groups, and used nontraditional data sources for decision-making. Broader implementation of these approaches, combined with increased interagency and international coordination and collaboration, should facilitate the rapid advancement of more effective CE assessment and ecosystem management in North America and elsewhere. 相似文献