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61.
METRO集团,世界领军零售公司之一,已经在26个国家落户.集团的贸易战略目标设定在向一个可持续性的、赢利的公司发展.在它的第一份可持续性报告(发表于2002年春季)里,集团的许多可持续性发展的相关活动非常醒目.智能物流系统和广泛的废物管理行动扎根于集团的环境实力之中.强调食品安全的世界采购方针和措施,是满足消费者要求产品符合社会和环境标准的两种手段.只要消费者能获得全面的信息,只要员工的积极性被调动起来并经过适当的培训,那么METRO集团在其可持续性报告中所列出的所有的可持续性目标最终就一定能实现.  相似文献   
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Participation is usually regarded as a good practice in environmental policymaking, but its effects on policy strategies are unclear. Based on literature research, surveys, and interviews with participants, the present paper assesses whether decisional participation in formulating Austria’s National Adaptation Strategy (NAS) was worth the effort. Assessed against the goals of the participation process, we find that it raised awareness for adaptation and facilitated an exchange among the participants and that it improved the content of the NAS. However, regarding the goal of enhancing the acceptance of and commitment to the NAS, we find that this has been achieved among those who participated but not among high-level policymakers who are responsible for implementing the NAS. We conclude that (decisional) participation has its benefits in formulating comprehensive policy strategies but that it is most likely not able to overhaul their well-documented weaknesses, among them weak political commitment and implementation failures.

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Although experiences with ecological restoration continue to accumulate, the effectiveness of restoration for biota remains debated. We complemented a traditional taxonomic analysis approach with information on 56 species traits to uncover the responses of 3 aquatic (fish, macroinvertebrates, macrophytes) and 2 terrestrial (carabid beetles, floodplain vegetation) biotic groups to 43 hydromorphological river restoration projects in Germany. All taxonomic groups responded positively to restoration, as shown by increased taxonomic richness (10–164%) and trait diversity (habitat, dispersal and mobility, size, form, life history, and feeding groups) (15–120%). Responses, however, were stronger for terrestrial than aquatic biota, and, contrary to our expectation, taxonomic responses were stronger than those of traits. Nevertheless, trait analysis provided mechanistic insights into the drivers of community change following restoration. Trait analysis for terrestrial biota indicated restoration success was likely enhanced by lateral connectivity and reestablishment of dynamic processes in the floodplain. The weaker response of aquatic biota suggests recovery was hindered by the persistence of stressors in the aquatic environment, such as degraded water quality, dispersal constraints, and insufficient hydromorphological change. Therefore, river restoration requires combined local- and regional-scale approaches to maximize the response of both aquatic and terrestrial organisms. Due to the contrasting responses of aquatic and terrestrial biota, the planning and assessment of river restoration outcomes should consider effects on both components of riverine landscapes.  相似文献   
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We test the hypothesis that echolocation behavior can be used to find the border between bat habitats. Assuming that bats react to background targets in “edge space” but not in “open space”, we determined the border between these two habitat types for commuting individuals of the parti-colored bat Vespertilio murinus. We recorded sequences of bats’ echolocation signals while they flew parallel to the walls of large buildings and to the ground and determined the signals’ average bandwidth, duration, and pulse interval. These parameters varied systematically with the estimated horizontal and vertical distances between the bats and the background. A distinct effect of horizontal distance to the background on echolocation behavior was found for horizontal distances of less than 6 m, thus indicating the border between edge and open space. Only a few bats flew at vertical distances below 5 m. However, enough passages at vertical distances of 5 m and above indicated that the vertical border is somewhere below a distance of 5 m. Within edge space, V. murinus reacted to the background by reducing signal duration, increasing bandwidth at closer distances, and often emitting one signal per wing beat. In open space, signal parameters did not vary as a function of distance to the background. There, V. murinus emitted the longest signals with the narrowest bandwidth and often made one or two wing beats without emitting a pulse. With our data we support with statistical methods the hypothesis that echolocation behavior reveals the border between the habitat types “edge” and “open space”.  相似文献   
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Temporal variations in protein, carbohydrate, and lipid levels were studied in a passive suspension feeder, the gorgonian Paramuricea clavata. The samples were collected every month for mature and immature colonies over a three-year period (1997–2000). The relationship between biochemical composition and reproductive output was examined on the basis of the 1998 and 1999 data. In female and male P. clavata colonies, the tissue displayed differences in lipid concentrations only in winter–spring, due to the high lipid levels attained by female colonies in this period. Immature colonies showed significant differences in lipid concentration only with respect to mature females in spring. There were clear seasonal trends in the lipid and carbohydrate levels in P. clavata, with maximum values in winter–spring [male lipid 212±75 SD μg mg−1 of organic matter (OM) and female lipid 274±103 SD μg mg−1 of OM; male and female carbohydrate 68±14 SD μg mg−1 of OM], coinciding with maximum food concentration/quality, and minimum values in summer–autumn (male and female lipid 155±57 SD μg mg−1 of OM; male and female carbohydrate 56±14 SD μg mg−1 of OM), coinciding with low food concentration/quality. The relationship between reproductive output and tissue concentrations of lipids, carbohydrates, and proteins was not straightforward, although there was an evident overlap of the lipid accumulation and the gonadal development. The results of this study show that protein, carbohydrate, and lipid levels may provide a record of episodes in the ecological cycle bearing on the trophic aspects of the target species. The results indicate that information on seasonal biochemical levels may explain benthopelagic coupling processes, provided factors such as natural diet, feeding rates, reproduction, and growth are well understood.  相似文献   
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Petrie et al. (1991) demonstrated a correlation between the degree of elaboration of peacocks' trains and their mating success, and also showed that this correlation occurred because females preferred to mate with the male that had the most elaborate train of those sampled on the lek. Although these data suggest that female choice is responsible for non-random mating in this species, they do not conclusively show that train morphology is the cue that females respond to, because they do not rule out the possible influence of another unidentified variable which is correlated with train elaboration. This paper presents an experimental test of the importance of the peacock's train in determining male mating success. If the number or arrangement of eye-spots in the peacock's train influences mating success, then changing the number of eye-spots should change mating success. This prediction was tested in an experiment where the trains of male peafowl (Pavo cristatus) were manipulated by removing a number of eye-spots between mating seasons. Peacocks with eye-spots removed showed a significant decline in mating success between seasons compared with a control group. This result, together with the observational data, supports the hypothesis that the peacock's train has evolved, at least in part, as a result of female choice.  相似文献   
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