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1.
Methods for defining and retrieving reference conditions for large rivers were explored with emphasis on hydromorphologic and biologic quality indicators. For a set of four large rivers in the European Western Plains ecoregion, i.e., the rivers Meuse, Loire, Allier, and Dordogne, reference reaches were selected based on geomorphologic characteristics. A survey of riparian land use, vegetation, and bed geometry was done for the selected reaches. Responses of the riparian landscape to hydromorphologic conditions were determined with a set of existing and newly developed measures of riparian dynamics and forest development. Strong correlations were observed at the reach and local levels between the ratios of width to depth and embankment and the developed measures of riparian dynamics and forest. Boundary conditions for riparian forest development were determined for the hydromorphologic and biologic indicators of riparian dynamics and vegetation structure. These conditions also proved useful for determining the presence of sustainable populations of Populus nigra and Salix purpurea. From this agreement between abiotic and biotic boundary conditions, a set of useful reference conditions was determined, and a framework for the definition of reference and good status conditions subsequently evolved. Finally, a proposal for assessment and monitoring the proposed indicators is discussed for its applicability.  相似文献   

2.
Given the projected threat that climate change poses to biodiversity, the need for proactive response efforts is clear. However, integrating uncertain climate change information into conservation planning is challenging, and more explicit guidance is needed. To this end, this article provides a specific example of how a risk-based approach can be used to incorporate a species’ response to climate into conservation decisions. This is shown by taking advantage of species’ response (i.e., impact) models that have been developed for a well-studied bird species of conservation concern. Specifically, we examine the current and potential impact of climate on nest survival of the Lewis’s Woodpecker (Melanerpes lewis) in two different habitats. To address climate uncertainty, climate scenarios are developed by manipulating historical weather observations to create ensembles (i.e., multiple sequences of daily weather) that reflect historical variability and potential climate change. These ensembles allow for a probabilistic evaluation of the risk posed to Lewis’s Woodpecker nest survival and are used in two demographic analyses. First, the relative value of each habitat is compared in terms of nest survival, and second, the likelihood of exceeding a critical population threshold is examined. By embedding the analyses in a risk framework, we show how management choices can be made to be commensurate with a defined level of acceptable risk. The results can be used to inform habitat prioritization and are discussed in the context of an economic framework for evaluating trade-offs between management alternatives.  相似文献   

3.
The climate change mitigation mechanism Reducing Emissions from Deforestation and Forest Degradation in developing countries (REDD+) is currently being negotiated under the United Nations Framework Convention on Climate Change (UNFCCC). Integrating biodiversity monitoring into REDD+ facilitates compliance with the safeguards stipulated by the UNFCCC to exclude environmental risks. Interviews with actors engaged in REDD+ implementation and biodiversity conservation at the national and sub-national level in Peru (n = 30) and a literature review (n = 58) were conducted to pinpoint constraints and opportunities for monitoring effects of REDD+ management interventions on biodiversity, and to identify relevant biodiversity data and indicators. It was found that particularly sub-national actors, who were frequently involved in REDD+ pilot projects, acknowledge the availability of biodiversity data. Actors at both the national and sub-national levels, however, criticized data gaps and data being scattered across biodiversity research organizations. Most of the literature reviewed (78 %) included indicators on the state of certain biodiversity aspects, especially mammals. Indicators for pressure on biodiversity, impacts on environmental functions, or policy responses to environmental threats were addressed less frequently (31, 21, and 10 %, respectively). Integrating biodiversity concerns in carbon monitoring schemes was considered to have potential, although few specific examples were identified. The involvement of biodiversity research organizations in sub-national REDD+ activities enhances monitoring capacities. It is discussed how improvements in collaboration among actors from the project to the national level could facilitate the evaluation of existing information at the national level. Monitoring changes in ecosystem services may increase the ecological and socioeconomic viability of REDD+.  相似文献   

4.
The Brambell Report of 1965 recommended that animals should have the freedom to stand up, lie down, turn around, groom themselves and stretch their limbs. The Farm Animal Welfare Council (FAWC) developed these into the Five Freedoms, which are a framework for the analysis of animal welfare. The Five Freedoms are well known in farming, policy making and academic circles. They form the basis of much animal welfare legislation, codes of recommendations and farm animal welfare accreditation schemes, and are the foundation of the Welfare Quality® assessment scheme. The Five Freedoms are also extensively employed for the education of veterinary and animal welfare science students. Hence they have proven to be of great practical utility. In this paper, the Five Freedoms framework is examined in terms of necessary and sufficient conditions for the analysis of animal welfare. Overall, the Five Freedoms are judged to be individually necessary and jointly sufficient as a framework for the analysis of animal welfare. FAWC has recently criticized the Five Freedoms for concentrating on negative aspects of welfare. However, it is shown here how the satisfaction of the Five Freedoms should lead to good welfare, from the animal’s point of view. The Five Freedoms are formulated as ideals of animal welfare. This has significant advantages that have likely contributed to their impact. However, the ideality of the Five Freedoms means that the framework is without power to determine what a satisfactory level of animal welfare is, in an ethical sense.  相似文献   

5.
Bear bile has long been used in the Asian traditional pharmacopoeia. Bear farming first started in China ~30 years ago in terms of reducing the number of poached bears and ensuring the supply of bear bile. Approximately 13,000 bears are today captivated on Asia’s bear farms: their teeth are broken and the claws are also pulled out for the sake of human safety; the bears are imprisoned in squeeze cages for years; and a catheter is daily inserted into a bear’s gall bladder or a tube is implanted inside its body in order to collect the dripped bile—captive bears moan in severe pain whenever the bile is extracted. When the bears cannot produce sufficient bile, they are often left to die of starvation. It must be impossible to justify the bile extraction from living bears because (1) medicinal/herbal alternatives are similar to bear bile; (2) there is no evidence to suggest that bear farming has any beneficial effects on wild bear populations; and (3) ethical problems lie not only in the painful bile extraction but also the whole lifecycle of captive bears. In conclusion, human welfare (health care) based on traditional medicine is upheld by sacrificing bear welfare. Since a trial calculation suggests that it is economically unfeasible to keep a proper balance between bear welfare and the traditional pharmacopeia, the cultivation of herbal alternatives seems to be a possible solution to phase out bear faming and maintain the practice of traditional medicine in Asia.  相似文献   

6.
7.
This paper discusses the emergent interest in risk communication as a strategy for disaster risk reduction. Communication plays an essential role in understanding risk, but studies suggest that people often do not respond in the way that risk experts anticipate. For risk communication to be effective, vulnerable communities need to understand risk within the local context as well as in terms of sustainability. Risk messages offer communities a way to enhance their collective knowledge of existing vulnerabilities, leading them towards alternative solutions for action. A longitudinal study of the Mano community development approach and its recovery from the 1995 Kobe earthquake illustrates how risk communication dynamics contributed to the community’s sustainable risk reduction. The study concludes that risk communication is a collaborative way for a community to work with risk experts, own their risk information, influence existing policies and practices, develop solutions to reduce vulnerability, and ultimately enhance a community’s capacity for managing future risk.  相似文献   

8.
The Platte River Basin consists of tributaries largely in Wyoming, Colorado and Western Nebraska, with the main stem in Central Nebraska. Critical wildlife habitat on the main stem requires additional in-stream flows. The watershed is one hosting multiple resources, a variety of users, and managed by an array of state and federal agencies. This study proposes a basis for securing in-stream flows for the Platte River. Candidate water supply mechanisms are suggested based on the way in which Casper, Wyoming secured water for its municipal needs. Canal lining is compared to a dam project, increasing reservoir storage, and purchasing water rights, with consideration also made for water pricing to reduce municipal use. Comparisons are based on economic efficiency, potential water conservation, and property rights criteria. Canal lining, coupled with demand management, is shown to conserve water best, given the set of efficiency and cost criteria for in-stream flow enhancement. The approach offers an opportunity to organize the water supply choice context in a transboundary watershed when quantitative information is limited.  相似文献   

9.
The Conversion of Cropland to Forest and Grassland Program (CCFG), which was initiated by the Chinese government in 1999, is a cropland retirement program with integrated objectives for ecological preservation and local development. The purpose of this article was to study the influencing factors of attitude and economic strategies in rural households toward the CCFG. Rural households’ knowledge, attitude and economic strategies toward the CCFG were investigated through a questionnaire survey in Qira, China. Influencing factors of attitude and strategies of households were analyzed using a logit model technique. The analysis indicated that household’s income level, environmental knowledge of the program, and program implementation were significant influencing factors in a household’s attitude toward the CCFG, while major influencing factors of household strategies were their regional background and availability of income generation sources. Meaningful association was not found between attitude and strategy choices. Rich households had more strategy choices, while poor households were usually confined to low input strategies with uncertain income. To sustain their livelihood, the poor need extra assistances in marketing, loan granting, employment training, information, and technical services.  相似文献   

10.
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