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41.
42.
Erratum     
Naturwissenschaften Aktuell  相似文献   
43.
This paper is part of a two-year study to investigate the feasibility of initiating a Clean Development Mechanism (CDM) project in an indigenous community of Eastern Panamá, Ipetí-Emberá. We use participatory mapping and matrices as well as household surveys to develop a land-use/land-cover baseline scenario and examine the role of local participation in assessing land-use change. In Ipetí, land-use change has not occurred in a linear way over the last decades, and our data unveils socio-economic factors as potential key drivers of change. The concordance that we observed between geographic information and individual and collective perceptions of land-use change substantiates the possibility of using local knowledge in the establishment of baseline data for CDM projects. Our calculations suggest that the total carbon (C) stocks in the Tierra Colectiva (TC) of Ipetí-Emberá in 2004 represents a 47% reduction from the estimated C stock at the onset of settlement in the early 1970’s. Results from the participatory assessments predict that, in 2024 and in absence of a CDM project, the C stocks will decline from 301,859 t C in 2004 to 155,730 t C, which constitutes a reduction of 52%. The scenario with CDM estimates C stocks of 305,853 t C for 2024, a value slightly superior to the 2004 value. In the TC there is ground to believe that cattle ranching is likely to become an ever more important activity as the population is young and growing and cannot easily move elsewhere. Forests tend to be cleared for cultivation while pastures are established on short fallows. Our baseline scenario underlines the potential for a CDM project to make a significant difference in the future C stocks of this landscape.  相似文献   
44.
A study of the relationship between natural hazards and climate change in the international context provides the background for a discussion of the expected changes. In the context of this global discussion, this paper reviews the current perspectives of those natural hazards that are likely to be influenced by climate change, using northern Canada as a regional case study. The northern implications of the United Nations Framework Convention on Climate Change are examined, including the status of climate change action by the northern territorial governments, the evolving role of indigenous people, and the responsibility for climate change impacts. The difficulties surrounding natural hazards research in remote locations, and the approaches of indigenous people to natural hazards are then presented. The paper concludes with a suggested policy approach for climate change and natural hazards in northern Canada, underscoring the need for more comprehensive adaptive strategies to complement the current tendency to focus on the mitigation of greenhouse gases produced in this region.  相似文献   
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Summary This paper describes a 13-weeks, third-year course in Environmental Planning and Management developed and taught by the authors. Initiated in 1969, the course consists of a mix of lectures, seminars, workshop/laboratory sessions and field-based projects. The objectives of the course are for students: to become aware of the need for, and the complexities of, environmental management; to be able to criticise constructively work done by environmental agencies and consultants, managers and decision makers; and to learn and apply some of the methods and techniques used in environmental management.Topics covered by the current syllabus are: concepts of resource and environment; constitutional aspects; international law and the environment; Australian and Canadian environmental legislation and agencies; human manipulation of ecosystems; energy subsidies; modification of biogeochemical cycles; population dynamics and cropping; fisheries; national parks and reserves—policies in different countries; international heritage areas; environmental assessment (including impact assessment, land evaluation, land capability and land suitability assessment); and regional, integrated land-use and environmental planning and management. Techniques taught include: field surveys and interviewing; laboratory analysis of selected water quality, sediment and soil parameters including nutrient concentrations, heavy metal and pesticide residues; and for some students, applications of geographic information systems (GIS) technology following preceding GIS courses.A major problem is selecting the most appropriate mix between the social and natural sciences—appropriate, first in terms of students' heterogeneous skills and backgrounds, and second, in terms of understanding the causes of environmental problems and issues, and devising practicable solutions.  相似文献   
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Enhanced bioremediation is quickly developing into an economical and viable technology for the remediation of contaminated soils. Until recently, chlorinated organic compounds have proven difficult to bioremediate. Environmentally recalcitrant compounds, such as polychlorinated biphenyls (PCBs) and persistent organic pesticides (POPs) such as dichlorodiphenyl trichloroethane (DDT) have shown to be especially arduous to bioremediate. Recent advances in field‐scale bioremedial applications have indicated that biodegradation of these compounds may be possible. Engineers and scientists at the Savannah River Site (SRS), a major DOE installation near Aiken, South Carolina, are using enhanced bioremediation to remediate soils contaminated with pesticides (DDT and its metabolites, heptachlor epoxide, dieldrin, and endrin) and PCBs. This article reviews the ongoing remediation occurring at the Chemicals, Metals, and Pesticides (CMP) Pits using windrow turners to facilitate microbial degradation of certain pesticides and PCBs. © 2003 Wiley Periodicals, Inc.  相似文献   
49.
The purpose of this study was to examine the factor structure of the transformational leadership model in human service teams. As the nature of this work environment mandates certain management‐by‐exception practices, patterns of correlations between perceptions of active and passive management‐by‐exception behaviors and transformational, transactional, and laissez‐faire leadership were of interest. 236 leaders and 620 subordinates from 54 mental health teams completed the Multifactor Leadership Questionnaire, form 8Y. Results suggest that active and passive management‐by‐exception factors are independent constructs. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
50.
With the increased use of electric and electronic equipment in our offices, our daily exposure to electromagnetic fields has become increasingly complex due to the great variety of the frequency content of the fields. Today focus has shifted from monitors as the dominating sources of electromagnetic fields to other electronic equipment, cabling, nearby substations, power lines and stray currents in buildings. In the last 5 years wireless communication has become common in our offices. These devices use radio frequency waves to communicate and are therefore sources of radio frequency fields in our offices. To a certain degree, they all add to the complicated issue of the extensive field frequencies found in offices. The exposure of office workers is generally considered to be low and not in conflict with the existing guidelines, but if a precaution approach is applied there are a number of measures that can be taken to reduce the electromagnetic fields in offices in order to obtain a good electrical environment.  相似文献   
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