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Sustainable development has been intensely debated for more than twenty years, but real progress of our societies to become more sustainable is very slow. Therefore this special issue provides a forum for critical perspectives of Sustainable Development Research and Practice. The papers are grouped into three clusters: a. Sustainability Science, b. Economic Problems and c. Corporate Contributions to Sustainable Development.Although a single special issue cannot address the entire array of issues pertaining to progress of sustainability related research, the selected papers highlight special aspects of sustainability research either due to their theoretical contributions or because they report on valuable empirical evidence. The main goal of sustainability research should be to contribute to our understanding of sustainability problems and to develop and help to implement solutions to solve them. This can be described as the relevance of sustainability research. A precondition to gain relevance is the rigor of sustainability science: it has to be based on solid scientific principles and methods. Additionally it has to be regarded that Sustainable Development is dynamic and that it has both normative and practical aspects. It is concluded that sustainability science and practice should be based upon these four central aspects: rigor, relevance, normative aspects and dynamic  相似文献   
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Breeding of golden hamsters is classically performed at thermal conditions ranging from 20 to 24 °C. However, growing evidence suggests that lactating females suffer from heat stress. We hypothesised that shaving females dorsally to maximise heat dissipation may reduce stress during reproduction. We thus compared faecal cortisol metabolites (FCM) from shaved golden hamster mothers with those from unshaved controls. We observed significantly lower FCM levels in the shaved mothers (F1,22?=?8.69, p?=?0.0075) pointing to lower stress due to ameliorated heat dissipation over the body surface. In addition, we observed 0.4 °C lower mean subcutaneous body temperatures in the shaved females, although this effect did not reach significance (F1,22?=?1.86, p?=?0.18). Our results suggest that golden hamsters having body masses being more than four times that of laboratory mice provide a very interesting model to study aspects of lactation and heat production at the same time.  相似文献   
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From a life history perspective, glucocorticoids secreted by the neuroendocrine system, integrating different sources of stress through an adaptive feedback mechanism, may have important consequences on individual fitness. Although stress responses have been the object of several investigations, few studies have explored the role of proximate mechanisms responsible for the potential trade-offs between physiological stress and life history traits integrating social and environmental stressors. In 2011 and 2012, we collected data on faecal cortisol metabolites (FCM) in a marked male population of Alpine chamois, within the Gran Paradiso National Park (Italy). Using a model selection approach we analysed the effect of potential etho-ecological stressors such as age, social status (territorial vs. non-territorial males), minimum temperature, snow depth and precipitation on FCM variation. To correctly interpret environmentally and socially induced stress responses, we conducted model selections over multiple temporal scales defined a priori: year, cold months, spring, warm months, mating season. Over the year, FCM levels showed a negative relationship with minimum temperature, but altogether, climatic stressors had negligible effects on glucocorticoid secretion, possibly owing to good adaptations of chamois to severe weather conditions. Age was negatively related to FCM during the rut, possibly due to greater experience of older males in agonistic contests. Social status was an important determinant of FCM excretion: while both the ‘stress of subordination’ and the ‘stress of domination’ hypotheses received some support in spring and during the mating season, respectively, previous data suggest that only the latter may have detrimental fitness consequences on male chamois.  相似文献   
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To investigate how the perceptions and behaviour of visitors to coral reefs are influenced by their prior experience and knowledge of marine life, a questionnaire-based study was undertaken at sites in the Ras Mohammed National Park and at Sharm El Sheikh, South Sinai, Egypt. It was evident that over the 10–20 years during which these reefs have deteriorated (mainly due to reef-flat trampling), there have been interrelated shifts in the nature of visitors making use of them. First, there has been a shift from experienced divers and snorkellers to inexperienced snorkellers and non-snorkellers with a poorer knowledge of reef biology. Second, there has been a shift in the predominant nationalities of visitors, from German and British, through Italian, to Russian. More recent user groups both stated and showed that they had less experience of snorkelling; they also showed less knowledge of marine life and less interest in learning about it. Visitor perceptions of both the state of the marine life on the reefs and the acceptability of current visitor numbers also varied between groups. More recent visitor groups and visitors with less knowledge were more satisfied with reef health. In general, however, visitor perceptions of reef health did not correlate well with actual reef conditions, probably because more experienced visitors preferred less impacted sites with which they were nevertheless less satisfied than inexperienced visitors at heavily impacted sites. More recent visitor groups were also less bothered by crowding on the shore or in the water. Consequently, the apparent “social carrying capacity” of sites seems to be increasing to a level well above the likely “ecological carrying capacity”.  相似文献   
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High-conservation-value forests (HCVFs) are critically important for biodiversity and ecosystem service provisioning, but they face many threats. Where systematic HCVF inventories are missing, such as in parts of Eastern Europe, these forests remain largely unacknowledged and therefore often unprotected. We devised a novel, transferable approach for detecting HCVFs based on integrating historical spy satellite images, contemporary remote sensing data (Landsat), and information on current potential anthropogenic pressures (e.g., road infrastructure, population density, demand for fire wood, terrain). We applied the method to the Romanian Carpathians, for which we mapped forest continuity (1955–2019), canopy structural complexity, and anthropogenic pressures. We identified 738,000 ha of HCVF. More than half of this area was identified as susceptible to current anthropogenic pressures and lacked formal protection. By providing a framework for broad-scale HCVF monitoring, our approach facilitates integration of HCVF into forest conservation and management. This is urgently needed to achieve the goals of the European Union's Biodiversity Strategy to maintain valuable forest ecosystems.  相似文献   
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Lanthanum-modified bentonite clay (Phoslock(?) is a lake remediation tool designed to strip dissolved phosphorus (P) from the water column and increase the sediment P-sorption capacity. This study investigated short term alterations in sediment elemental composition and sediment P-fractions based on sediment cores taken 2 days before and 28 days following the application of 24 t of Phoslock? to a 9 ha, man-made reservoir. Following the application, sediment lanthanum (La) content increased significantly (p < 0.05; n = 4) in the top 8 cm of the sediment, thereby theoretically increasing sediment P-binding capacity on the whole reservoir scale by 250 kg. Mass balance calculations were used to estimate the theoretical binding of release-sensitive P (P(mobile); sum of 'labile P', 'reductant-soluble P' and 'organic P' fraction) by La across the top 4 cm and 10 cm depth of sediment. The amended mass of La in the sediment had the potential to bind 42% of P(mobile) present in the top 4 cm or 17% of P(mobile) present in the top 10 cm. However, with the exception of a significant increase (p<0.05; n=4) in the 'residual P' fraction in the top 2 cm, sediment P-fractions, including P(mobile,) did not differ significantly following the Phoslock? application. Experimental P-adsorption studies indicated P-saturation values for Phoslock? of 21,670 mg P kg?1 Phoslock?. Sequential extraction of P from saturated Phoslock? under laboratory conditions indicated that around 21% of P bound by Phoslock? was release-sensitive, while around 79% of bound P was unlikely to be released under reducing or common pH (5-9) conditions in shallow lakes. Applying Phoslock? is, therefore, likely to increase the P-sorption capacity of sediments under reducing conditions.  相似文献   
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Summary. Endosymbiotic bacteria implicated in pederin production of Paederus (+)-females (Coleoptera: Staphylinidae) can be transmitted horizontally within and less frequently among the three species analyzed (P. melanurus, P. riparius, P. sabaeus). The 16S rDNA isolated from (+)-females reveals closely related bacterial sequences in the three species as well as in Paederus fuscipes and Paederidus ruficollis. This confirms the association of the undescribed endosymbiont and pederin biosynthesis in 5 of the 13 species that have been shown to contain the substance. In spite of the high sequence identities (> 99.5%), which suggest one species of endosymbiont, some of the heterospecific hosts were incompatible. This indicates adaptation and specific preferences of the endosymbiont for their natural host. Received 5 December 2001; accepted 11 March 2002.  相似文献   
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The intentional dissemination of Bacillus anthracis (anthrax) spores at multiple locations in the United States in the fall of 2001 resulted not only in several deaths and illnesses (including psychological effects), but likely changed lifestyles and attitudes, and increased the public's awareness of individual vulnerability. While federal resources had previously been committed to preparing local public health agencies for counter‐terrorism activities and to enhance environmental and medical response, these release episodes have increased the consistency of environmental and medical response activities, and increased government resources for homeland security. This article abstracts current information from many sources that summarize the environmental responses to the anthrax releases. The article discusses the international agreements and the U.S. regulations concerning biological weapons, the characteristics of the anthrax organism, potential exposure pathways, adverse health conditions resulting from inhalation exposure, the environmental response to two specific release episodes, environmental sampling and analytical procedures, recommended personal protective equipment, and the subsequent federal efforts to improve response capabilities. © 2003 Wiley Periodicals, Inc.  相似文献   
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Towards a Formal Framework of Vulnerability to Climate Change   总被引:7,自引:0,他引:7  
There is confusion regarding the notion of “vulnerability” in the climate change scientific community. Recent research has identified a need for formalisation, which would support accurate communication and the elimination of misunderstandings that result from the use of ambiguous terminology. Moreover, a formal framework of vulnerability is a prerequisite for computational approaches to its assessment. This paper presents an attempt at developing such a formal framework. We see vulnerability as a relative concept in the sense that accurate statements about vulnerability are possible only if one clearly specifies (1) the entity that is vulnerable, (2) the stimulus to which it is vulnerable and (3) the preference criteria to evaluate the outcome of the interaction between the entity and the stimulus. We relate the resulting framework to the Intergovernmental Panel on Climate Change conceptualisation of vulnerability and two recent vulnerability studies. This paper is dedicated to the memory of Gerhard Petschel-Held, whose pioneering work on syndromes of global change has been a source of inspiration for us and for others across various schools of thought on vulnerability.  相似文献   
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