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711.
This paper provides a broad evaluation of the implications of market‐based conservation (MBC) strategies from economic, social and ecological perspectives. After reviewing the economic theory that underlies MBC initiatives, we develop a list of approaches that have been labeled as “market‐based”, and categorize them according to the degree to which they are free‐standing markets or require the intervention of the state. A multidisciplinary critique reveals the potential problems and pitfalls of MBC are due to a lack of ability to deal with dynamic systems in the real world. The dynamics of these three systems can undermine the intended goals of MBC.  相似文献   
712.
秦岭在中华文明的繁衍和发展过程中发挥了重要作用,被誉为"中华龙脉"。秦岭既是中国南北分界线,也是"天然中药库"和"世界生物基因库",在以建设文明生态环境为主旋律的新时代,秦岭南北麓依然出现了不同程度的无序开发和违章建设别墅等有悖生态文明建设的乱象,如何保护秦岭,协同推进秦岭生态文明建设具有非凡的意义。为此,本文从人类社会发展史和科学史维度上,阐述了生态文明与原始文明、农耕文明和工业文明各阶段在解决的关键问题、文明的标志与内涵、人与自然的关系等方面的本质区别;从生态系统服务功能维度上(水源涵养、环境净化、生物多样性维护、生物固碳与气候调节等),阐明了秦岭生态文明建设的重要意义;从思想、行动和科学三个维度上,指出了秦岭生态文明建设必须提高思想认识,一以贯之习近平生态文明思想,提高政治站位,与党中央保持高度一致,用系统论思想制定科学规划,以水环境、土壤环境、大气环境、植被以及野生珍稀动植物的保护为根本目标,从工业活动、农业活动、资源开发利用、人类日常生活干扰等多个方向协同推进,为中国社会可持续发展提供生态保障。  相似文献   
713.
任滋禾  白昱  周律 《环境科学学报》2019,39(3):996-1005
针对目前我国工业企业节水潜力分析准确程度不足的现状,以纺织印染企业为对象,根据水足迹评价方法建立了印染企业产品水足迹精确测算方法,从产品层面说明回用水和雨水收集对于水足迹的削减作用.结果表明,应用水回用及雨水收集利用后,单位产品新鲜水用量降低了11.3%,单位产品总工业用水量降低了10.4%.本研究将水平衡分析、水足迹评价与印染企业自身特点相结合,为企业内产品生产层面的节水分析提供了依据,并为企业的精细化节水路线设计提供了支持.  相似文献   
714.
Incentive-based mechanisms are regarded as efficient instruments to reconcile conservation and development. This win-win objective has been difficult to accomplish; cross-compliance has, therefore, been suggested as a mechanism to ensure sustainability. Cross-compliance, which requires producers to conform to production regulations and environmental standards to qualify for direct payments, has been a popular instrument in the Common Agricultural Policy (CAP) reform. Since 1990, cross-compliance has been the main characteristic of policy design in Sami reindeer husbandry in Finnmark, Norway. All direct transfers to the Sami pastoralists have been connected to harvesting demands to decrease the number of reindeer and to conserve pastures. The content of these incentive-based mechanisms are decided through negotiated agreements with the Sami Reindeer Herders' Association of Norway (NRL), and the regulation of reindeer numbers and access to pastures are delegated to co-management boards. Despite the participation of the Sami pastoralists in shaping these policies, win-win objectives have not been achieved. Although the cross-compliance program could have been improved by payment for graded results, the lack of regulations by the administration or co-management boards is more likely to be the cause of failure to reach sustainability. Despite the long-term failures of the cross-compliance program, policies have been slow to change. We might attribute this delay to the NRL's strong position in the negotiated agreements. In general, we argue that the success of the cross-compliance program depends on a well-functioning governance system that can implement regulations and sanctions if incentives do not work as intended.  相似文献   
715.
This paper analyses both the processes of adoption and diffusion of the practice of using the chopped residues of pruning as mulch in the olive orchards of the Southern Spanish province of Granada, one of the major olive-producing areas in the world. Many olive groves in the area are located on steep areas where the risk of soil erosion is high. A majority of farmers have adopted no tillage, as an alternative to traditional tillage, combined with either vegetation soil covers or, more frequently, using the chopped pruning residues as mulch. The data used comes from a survey carried out in 2005 to 215 olive farmers. From farmers' responses we estimate a binomial probit model to identify some socio-economic and institutional factors related to the decision to use the practice of mulching on a regular basis. We also estimate several diffusion models that describe the spatial and temporal spread of mulching among farmers. Our results show that mulching using the pruning residues is adopted by 43% of the surveyed farmers. The diffusion process of this practice has been very intense since the middle nineties, and seems to have been based on the interactions among farmers in the area of study rather than in other external source of information. Some of the relevant identified factors that affect the probability of adoption of this practice are farmer's experience, the level of soil degradation in the farm or the continuity of farming by some relative.  相似文献   
716.
Recovery plans are the main documents supporting management decision-making for threatened species. We evaluated Australian recovery plans to assess their appropriateness as conservation and management planning instruments. Six legislative requirements (species information and general requirements, species distribution and location, known and potential threats, objectives, performance criteria and actions, duration of the plan, and estimated costs of plan implementation) were used to assess the degree of compliance of recovery plans with the relevant legislation. We assessed all 236 official recovery plans which had been adopted as at January 2006. The results showed that plans were most compliant regarding the setting of objectives, performance criteria, recovery actions, and duration of plan. Most plans included a single performance criterion that was generally related to the population status of target species. Improvement is required in relation to identification of current threats and critical habitats, and the establishment of basic elements of monitoring and evaluation for measuring recovery progress. Gaps in ecological information are the main factors affecting adequate compliance with legislative requirements as opposed to managerial information (e.g. clarity in establishing the implementation schedule, costs and resource allocation). Planning deficiencies could be addressed by improving the recovery planning guidelines and more carefully reviewing the drafting and adoption of new plans.  相似文献   
717.
基于通量守恒原理的水质监测非统计不确定性研究   总被引:1,自引:0,他引:1  
水环境动态监测过程中,结果存在非统计不确定性.以北京市密云水库曹家路小流域安达木河部分汇流河段为研究对象,结合水质和流量数据,分析了单次监测中水质存在的偶然误差下限值,去除其粗大值,以其均值表征动态监测过程中的非统计不确定性.由于研究的汇流河段尺度小,水流经过时间短,迁移转化过程可以忽略,建立的基于通量守恒原理的非统计...  相似文献   
718.
张启东  谢强  杨晗  王蒙  徐玮 《四川环境》2013,32(2):42-45
通过对四姑娘山国家级自然保护区岷江冷杉林地表土壤和林下枯落物的实验分析,得出四姑娘山自然保护区岷江冷杉林0~40cm深度的土壤层最大贮水量为1694.8 t/hm2,林下枯落物最大持水量为233 t/hm2。四姑娘山自然保护区岷江冷杉林土壤及枯落物持水的最大值为1927.8 t/hm2。  相似文献   
719.
建设和实现美丽中国是一个系统工程,要通过建设资源节约型环境友好型城市这一重大举措来实现。根据新乡市高能耗、高物耗、高污染的产业仍占较大比重,粗放型的经济增长方式没有得到根本转变的现实情况,提出了建设资源节约型环境友好型城市应着重解决的几个问题,并提出了相应的对策建议,对于新乡市加快经济结构调整,实现可持续发展和全面建成小康社会的目标具有重要意义。  相似文献   
720.
综述国内外烟气余热利用技术的研究及应用现状,主要包括热能直接回收、吸收式制冷、有机朗肯循环和温差发电等方式。结合气田开采实际,分析讨论各类余热利用技术在气田增压机组烟气余热利用中的应用潜力和发展方向。在选择余热利用方案时,应结合气田增压机组现有条件、机组性能以及运行模式等因素进行综合评估。  相似文献   
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