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211.
The Clean Development Mechanism (CDM) was introduced by the Kyoto Protocol to provide a financial incentive to establish project activities in developing countries for reducing greenhouse gas emissions while also fostering sustainable development. This article shows that waste management project activities play an important role in achieving the aims of the CDM. It describes how these activities have to prove additionality, how the emission reductions must be calculated and monitored in order to be eligible and in order to lead to Certified Emission Reductions (CERs). The article further provides an analysis about the various challenges that are involved in applying the CDM scheme to waste management project activities, which require a new specific set of technical skills and regulatory standards.  相似文献   
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Results from the literature concerning feathers as a matrix for heavy metal accumulation were presented. Especially problems like the differentiation between endo and exogenous contributions, cleaning procedures or the right choice of feather parts were described. The question of the use of feathers for monitoring air, food or bird contamination is also discussed, as well as the advantages or disadvantages of this matrix in comparison to other methods.  相似文献   
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A straightened stream stretch with poor habitat heterogeneity was divided into a “control” section with a low amount of submerged woody debris and an experimentally “wood-enriched” downstream section to study the effect of enhanced habitat diversity on the benthic invertebrate community. The downstream section was enriched by fixing 25 wood packages constructed from 9–10 branches on the stream bottom. Succession processes occurring in the two stream sections were compared by chironomid exuviae drift from July to November 2000 and from April to August 2001. During the first sampling period, more drifting chironomid exuviae (medians of control vs. wood-enriched: 446 vs. 331, no significant difference) and total number of taxa (44 vs. 36, Wilcoxon signed-rank test P = 0.019) were recorded for the control section. Although species compositions of both stream sections were highly similar (Sørensen index: 0.83) the diversity in the wood-enriched section was distinctly lower compared to the control section (Shannon–Weaver index: 1.19 vs. 1.50). During the second sampling period, exuviae numbers remained higher in the control section (median: 326 vs. 166), but total numbers of taxa were nearly equal (51 vs. 49), as well as species diversity (Shannon–Weaver index: 1.67 vs. 1.64). The lower chironomid diversity observed during the first sampling period coincided with a gradual but significant change of the streambed morphology in the wood-enriched section. There, the initially more U-shaped profile (V/U = 0.81 ± 0.37) had turned into a pronounced V shape (V/U = 1.14 ± 0.21), whereas the control section retained its unaltered U shape (V/U = 0.62–0.75). This small-scale study on experimental of woody debris in sandy lowland streams showed that the negative impact of increased hydraulic disturbance of the existing streambed more than outweighed any positive impact resulting from the increase in woody debris.  相似文献   
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People suffering from various symptoms while in air-conditioned rooms often show sensitizations to fungi that can be isolated when the fungi are dremoved from air conditioners. By using specific challenge tests it was shown that fungal spores in air conditioners can evoke allergic symptoms. Hyposensitization was the specific therapy prescribed for such allergic reactions. After hyposensitization therapy, more than 70% of the patients so treated could live and work again in air-conditioned rooms without developing specific symptoms.  相似文献   
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Biodiversity is essential for multiple aspects of human life and well-being, but many current assessments of the functioning of biodiversity and ecosystems, understanding of risks posed by environmental change and the best practice of their management of ecosystems are lacking a unified scientific and conceptual basis. Methods such as scenario analysis, and terms such as ecosystem services, are widely used, but their meaning is understood in many different ways depending on context, user needs and experience of researchers. In order to advance the conceptual basis for ecosystem analysis and management in a rapidly changing world, as well as the ability of young scientists to reflect upon these concepts, we have organised five 2-week-long summer schools in Peyresq, a remote village in the Southern French Alps. In total 173 participants have worked intensively with 69 experienced researchers and a team of conveners and tutors in order to discuss a broad range of views on topics on ecosystem analysis and functioning. Topics ranged from conditions of and threats to various ecosystems due to environmental change, models and scenarios for assessment, stakeholder perceptions and needs for information, to the social and economic contexts for biodiversity. We report our experience from these schools, present the training concept which has emerged from them and suggest lines of further development.
Wolfgang CramerEmail:
  相似文献   
218.
Trends of summer precipitation and summer temperature and their influence on trends in summer drought and area burned in British Columbia (BC) were investigated for the period 1920–2000. The complexity imposed by topography was taken into account by incorporating high spatial resolution climate and fire data. Considerable regional variation in trends and in climate–fire relationships was observed. A weak but significant increase in summer temperature was detected in northeastern and coastal BC, whereas summer precipitation increased significantly in all regions—by up to 45.9 %. A significant decrease in province-wide area burned and at the level of sub-units was strongly related to increasing precipitation, more so than to changing temperature or drought severity. A stronger dependence of area burned on precipitation, a variable difficult to predict, implies that projected changes in future area burned in this region may yield higher uncertainties than in regions where temperature is predominantly the limiting factor for fire activity. We argue that analyses of fire–climate relationships must be undertaken at a sufficiently high resolution such that spatial variability in limiting factors on area burned like precipitation, temperature, and drought is captured within units.  相似文献   
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