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The consideration of time in environmental research allows new insights into the fundamentals of environmental research and new pathways for perceiving and answering questions which might arise in environmental research. In order to take this all into account, one must realize that ecological systems have a history and that both the spatial aspects and the chronological expansion of these systems must be taken into consideration. Considering temporalities, rhythms and time scales as well as their interdependencies in environmental research and environmental protection enables us to obtain a better understanding. The significance of relationships and functions in ecological systems can be perceived better as well. The impact of pollutants as well as the outcome of human actions in ecology, and in economics and politics, is consequently mandatory for not only a spatial, but also for the involved temporal scales. 相似文献
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Population trends from the Breeding Bird Survey are widely used to focus conservation efforts on species thought to be in decline and to test preliminary hypotheses regarding the causes of these declines. A number of statistical methods have been used to estimate population trends, but there is no consensus as to which is the most reliable. We quantified differences in trend estimates or different analysis methods applied to the same subset of Breeding Bird Survey data. We estimated trends for 115 species in British Columbia using three analysis methods: U.S. National Biological Service route regression, Canadian Wildlife Service route regression, and nonparametric rank-trends analysis. Overall, the number of species estimated to be declining was similar among the three methods, but the number of statistically significant declines was not similar (15, 8, and 29 respectively). In addition, many differences existed among methods in the trend estimates assigned to individual species. Comparing the two route regression methods, Canadian Wildlife Service estimates had a greater absolute magnitude on average than those of the U.S. National Biological Service method. U.S. National Biological Service estimates were on average more positive than the Canadian Wildlife Service estimates when the respective agency's data selection criteria were applied separately. These results imply that our ability to detect population declines and to prioritize species of conservation concern depend strongly upon the analysis method used. This highlights the need for further research to determine how best to accurately estimate trends from the data. We suggest a method for evaluating the performance of the analysis methods by using simulated Breeding Bird Survey data. 相似文献
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This research extends recent studies of the relationship between characteristics of jobs and patterns of workers' alcohol consumption. Working within a ‘generalization perspective ’whereby job conditions are seen as having important effects on the mental health and behaviors of workers in non-work settings, the current research derives and tests a model of four job-related factors as they influence three aspects of alcohol use; the simple frequency—quantity of drinking, escapist-oriented reasons for drinking, and a combination of heavier drinking with escapist-oriented definitions which is labeled ‘self-medication’. Analyses of data drawn from the 1973 Quality of Employment Survey (QES) indicate that the relationship between jobs and drinking behavior is more complex than previously conceptualized. Specifically, we find evidence that for working men characteristics of jobs affect levels of alcohol consumption and the incidence of self-medicating drinking. These findings support and refine job-based explanations of drinking behavior. The implications of these findings for subsequent research and model-specification are discussed. 相似文献
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Peter Martin 《Environmental management》1991,15(6):773-783
Substantial land degradation of agricultural catchments in Australia has resulted from the importation of European farming
methods and the large-scale clearing of land. Rural communities are now being encouraged by government to take responsibility
for environmental care.
The importance of community involvement is supported by the view that environmental problems are a function of interactions
between people and their environment. It is suggested that the commonly held view that community groups cannot care for their
resources is due to inappropriate social institutions rather that any inherent disability in people.
The communicative catchment is developed as a vision for environmental care into the future. This concept emerges from a critique
of resource management through the catchment metaphors of the reduced, mechanical, and the complex, evolving catchment, which
reflect the development of systemic and people-centered approaches to environmental care. The communicative catchment is one
where both community and resource managers participate collaboratively in environmental care. A methodology based on action
research and systemic thinking (systemic action research) is proposed as a way of moving towards the communicative catchment
of the future. Action research is a way of taking action in organizations and communities that is participative and informed
by theory, while systemic thinking takes into account the interconnections and relationships between social and natural worlds.
The proposed vision, methodology, and practical operating principles stem from involvement in an action research project looking
at extension strategies for the implementation of total catchment management in the Hunter Valley, New South Wales. 相似文献
388.
Martin G. Beyer 《Natural resources forum》1991,15(2):118-122
The Global Consultation on Safe Water and Sanitation for the 1990s was an outstanding opportunity for participants from 102 developing countries along with over 60 External Support Agencies (ESA) to assess the experiences of the International Drinking Water Supply and Sanitation Decade 1981–1990 (IDWSSD) and to reach a consensus on strategies and approaches for complete and effective coverage of water supply and sanitation. The resulting New Delhi Statement summarizing the conclusions and recommendations of the Global Consultation was presented to the General Assembly in autumn 1990. As one of the positive results, the New Delhi Consultation agreed that the UN Agencies and other bodies should continue the coordination work of the Steering Committee for Water Supply and Sanitation. It also provided a basis for the restructuring and consolidation of the new Collaborative Council for Water Supply and Sanitation, which will form a continuous consultative body for all UN agencies, NGOs, other external support agencies and developing countries concerned with the water sector. 相似文献
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