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891.
Beach conservation and management on the high-value French Riviera in southeastern France have had mixed fortunes in shoreline economic development strategies over the past half century. Prior to 1965, socio-economic growth related to immigration and tourism resulted in considerable pressure on the coastal zone, leading in particular to beach erosion and degradation of beach environmental quality. Between 1965 and 1980, over 20% of the 132 km-long French Riviera was permanently altered through the implantation of yachting harbours and reclamation fill structures, while beach-based recreation had a rather low ranking as a development choice, except in the two major resorts of Cannes and Nice which exhibit a densely urbanized seafront. On this preponderantly boldrocky coast, the mediocre recreational value inherited by many of the beaches from the regional geologic setting, and from development pressures and earlier errors in coastal management, left them vulnerable to appropriation and so-called ‘valorization’ by yachting harbour and estate developers. Over the last decade, artificial shoreline development has virtually ceased, in response to several more or less interrelated factors. These include relative stagnation of socio-economic growth, increasing development and maintenance costs of yachting harbours, saturation of the yachting harbour market as a result of the burgeoning of new, often cheaper, resorts and of reconversion of commercial and shipbuilding ports to leisure ports in the Mediterranean, more stringent legislation, since 1986, on the implantation of residential and major engineering structures on the coastline, pressure for conservation of the cultural and environmental heritage, and greater demand for beach recreational space. This situation has forced a diversification of shore-based activities, as it has been realised that better managed beaches may balance economic aspirations while contributing to enhanced environmental quality and sensible shoreline conservation. This change in strategy has entailed considerable efforts and money on the improvement of coastal water quality, the provision of amenities for beach-goers, and especially the nourishment of eroding beaches and the creation of several artificial beaches. The extent to which beaches will continue to play a role in the sustainable development of French Riviera resorts will depend largely on the capacity of local authorities to maintain environmental quality in the face of inherited and persistent handicaps such as beach erosion.  相似文献   
892.
Parasite success typically depends on a close relationship with one or more hosts; therefore, attributes of parasitic infection have the potential to provide indirect details of host natural history and are biologically relevant to animal conservation. Characterization of parasite infections has been useful in delineating host populations and has served as a proxy for assessment of environmental quality. In other cases, the utility of parasites is just being explored, for example, as indicators of host connectivity. Innovative studies of parasite biology can provide information to manage major conservation threats by using parasite assemblage, prevalence, or genetic data to provide insights into the host. Overexploitation, habitat loss and fragmentation, invasive species, and climate change are major threats to animal conservation, and all of these can be informed by parasites.  相似文献   
893.
With the intention of securing industry-free land and seascapes, protecting wilderness entered international policy as a formal target for the first time in the zero draft of the Post-2020 Global Biodiversity Framework under the Convention on Biological Diversity. Given this increased prominence in international policy, it is timely to consider the extent to which the construct of wilderness supports global conservation objectives. We evaluated the construct by overlaying recently updated cumulative human pressure maps that offer a global-scale delineation of industry-free land as wilderness with maps of carbon stock, species richness, and ground travel time from urban centers. Wilderness areas took variable forms in relation to carbon stock, species richness, and proximity to urban centers, where 10% of wilderness areas represented high carbon and species richness, 20% low carbon and species richness, and 3% high levels of remoteness (>48 h), carbon, and species richness. Approximately 35% of all remaining wilderness in 2013 was accessible in <24 h of travel time from urban centers. Although the construct of wilderness can be used to secure benefits in specific contexts, its application in conservation must account for contextual and social implications. The diverse characterization of wilderness under a global environmental conservation lens shows that a nuanced framing and application of the construct is needed to improve understanding, communication, and retention of its variable forms as industry-free places.  相似文献   
894.
The global whaling debate is one of the most well-known environmental disputes; despite the continued moratorium, both whaling and conflict continue. This endless discord has been criticised as deleterious to whale conservation and as imperialistic towards whaling communities. The history of the whaling debate is examined through the lens of cultural theory (CT). CT argues that there is productive potential in respectful interaction between different perspectives on an environmental issue. Using CT, modern whaling past and present is reconstructed, tracking how different actors have come to prominence, altering the nature of the policy landscape through their actions. Since the onset of modern whaling, whales and whaling practice have been conceived in narrow terms, depending on the dominance of particular actors on either side of the debate. Proposed solutions to the impasse are assessed according to the maxims of CT.  相似文献   
895.
运用价格杠杆,促进环境保护产业的发展   总被引:2,自引:0,他引:2  
环境保护产业作为“朝阳产业”,正在成为新的经济增长点。应运用价格杠杆,在建设骨干企业集团、健全环境保护产品市场体系、排污收费制度、价格信息服务等方面,推动环保产业的发展  相似文献   
896.
ABSTRACT: The use of scientific knowledge in environmental policy making is an important topic. However, the relation between knowledge producers and policy makers is not a straightforward producer-user relationship. The development of a national desiccation policy in the Netherlands and the implementation of desiccation plans in local situations are used as a case study to investigate the knowledge policy relationship. Three theoretical explanations were used to analyze this case: a difference between the cultures of producers and users; a different rationality of the policy making and research processes; and processes of social construction of problem definitions which imply that different knowledge stocks are used depending on the framing of the policy problem. Emergence of the policy issue at the national level is demonstrated to develop in close interaction between knowledge producers and policy makers, while the interactions at the local level were more based on integration of expert knowledge through personal expertise and closely tied to the development of management plans. This case study thus reveals a difference between general knowledge supporting measures at the national policy level and the way in which specific knowledge is applied in local cases. Therefore more attention should be paid to the translation of policy problems from rather high levels of political authority to the conceptualization at lower management levels. A final conclusion is that knowledge use in Dutch desiccation policy can be understood by pointing to multiple theoretical perspectives. The rational actor model and a construc-tivist perspective turned out to be especially useful in explaining the different ways knowledge was used at the national and the local level.  相似文献   
897.
四川盆地降水背景点及其降水化学组份的研究   总被引:5,自引:2,他引:5  
本文对四川自然保护区降水化学组份的研究,作为四川盆地的酸雨背景值,并与国内其它降水背景值进行比较。研究结果表明四川降水背景值pH>5.6,pH值变化相对比较稳定,降水化学组份浓度较低,也说明盆地外来源的污染物对盆地内的贡献是不明显的。  相似文献   
898.
States have the potential to play a major role in moving water conservation from conferences and reports that identify its advantages to actual practice. The research identifies four generic “strategies” that categorize the states' approaches toward conservation and reports on the states' current conservation activities. The four strategies are: reliance on agricultural advisors, leverage incentives, performance standards, and mandatory actions. Four levels of state conservation activity exist. California and Florida maintain the most extensive programs; Arizona, Massachusetts, New Jersey, North Carolina, and Oklahoma also have numerous programs but significantly lower staff commitments; eight additional states maintain more modest conservation effotts. Elsewhere, state directed conservation actions remain minimal and limited to those provided as agricultural advice. The study found support for water conservation the norm among water supply planners.  相似文献   
899.
本文根据我国珍稀濒危植物的保护现状和管理工作中存在的问题,系统地探讨了加强我国珍稀濒危植物和野生植物资源保护的政策措施。文中提出一系列具体、有效的政策构思,以及建立政府有关主管部门对珍稀濒危植物协调管理的体制等。  相似文献   
900.
The Thar Desert of North-west India has sprung into prominence recently because of nuclear testing in 1998. It occupies about 3 million km2 of diverse habitat. Each of the various habitats and landforms in the desert supports distinctive plants. 682 plant species have been identified including 107 grasses. Plants are removed for fuel, fodder, fencing and other farming, domestic and commercial purposes. There are about 200 species of plants with recognised medicinal uses in the desert. The medicinal usefulness of others is yet to be established. Commiphora wightii, Withania somnifera and Urginia indica have high glycoside content and are valued for gums and used in ayurvedic medicines for enhancing mental retention and memory enhancement. Such plants are being indiscriminately exploited for fuelwood.  相似文献   
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