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311.
The objective of this paper is to investigate the relationships among rural-urban migration, rural household income and sustainable development in rural areas of China. The typical case study is done and 288 questionnaires are collected from five villages in Hebei and Guangxi provinces, China. The migration and remittance status, household income and sustainable development of rural areas are analyzed on the basis of questionnaires. Rural-urban migration is becoming a part of routine life in rural areas. And remittance is an important component in rural household income. Rural-urban migration increases the arable land area per labor, which releases the tight human-land relationship in villages. In total, the migration increases the rural household income and accelerates the sustainable development of rural areas. 相似文献
312.
渤海区域生态补偿机制的研究 总被引:14,自引:0,他引:14
生态系统方法是保护和管理自然资源的新理念,得到世界各海洋大国的普遍关注和认可。生态系统方法要求运用生态补偿机制。构建海洋生态补偿机制的基本思路是:①根据海洋生态系统服务功能变化及其对利益相关者的影响界定补偿主体和补偿对象:②补偿途径以财政转移支付和环境资源税费为主;③遵循理论计算值与现有实践相结合的原则制定补偿标准。围绕影响渤海生态系统健康的关键是人类活动.提出了构建渤海区域生态补偿机制的初步设想。主要包括:改革现有“排污收费制度”。提高收费标准,增强制度的生态补偿效力。以减少陆源污染物排海;建立流域和海域之间的用水生态补偿机制。以增加入海淡水量;推广“退渔还湿”的生态补偿政策;加大资金投入.强化现有渔业生态补偿政策;以同区域内的土地价格为参照。对围海造地收取生态补偿金。 相似文献
313.
DARREN M. SOUTHWELL ALEX M. LECHNER† TERRY COATES‡ BRENDAN A. WINTLE§ 《Conservation biology》2008,22(4):1045-1054
Abstract: Whenever population viability analysis (PVA) models are built to help guide decisions about the management of rare and threatened species, an important component of model building is the specification of a habitat model describing how a species is related to landscape or bioclimatic variables. Model-selection uncertainty may arise because there is often a great deal of ambiguity about which habitat model structure best approximates the true underlying biological processes. The standard approach to incorporate habitat models into PVA is to assume the best habitat model is correct, ignoring habitat-model uncertainty and alternative model structures that may lead to quantitatively different conclusions and management recommendations. Here we provide the first detailed examination of the influence of habitat-model uncertainty on the ranking of management scenarios from a PVA model. We evaluated and ranked 6 management scenarios for the endangered southern brown bandicoot ( Isoodon obesulus ) with PVA models, each derived from plausible competing habitat models developed with logistic regression. The ranking of management scenarios was sensitive to the choice of the habitat model used in PVA predictions. Our results demonstrate the need to incorporate methods into PVA that better account for model uncertainty and highlight the sensitivity of PVA to decisions made during model building. We recommend that researchers search for and consider a range of habitat models when undertaking model-based decision making and suggest that routine sensitivity analyses should be expanded to include an analysis of the impact of habitat-model uncertainty and assumptions. 相似文献
314.
Abstract: Even under the most optimistic scenarios, during the next century human‐caused climate change will threaten many wild populations and species. The most useful conservation response is to enlarge and link protected areas to support range shifts by plants and animals. To prioritize land for reserves and linkages, some scientists attempt to chain together four highly uncertain models (emission scenarios, global air–ocean circulation, regional circulation, and biotic response). This approach has high risk of error propagation and compounding and produces outputs at a coarser scale than conservation decisions. Instead, we advocate identifying land facets—recurring landscape units with uniform topographic and soil attributes—and designing reserves and linkages for diversity and interspersion of these units. This coarse‐filter approach would conserve the arenas of biological activity, rather than the temporary occupants of those arenas. Integrative, context‐sensitive variables, such as insolation and topographic wetness, are useful for defining land facets. Classification procedures such as k‐means or fuzzy clustering are a good way to define land facets because they can analyze millions of pixels and are insensitive to case order. In regions lacking useful soil maps, river systems or riparian plants can indicate important facets. Conservation planners should set higher representation targets for rare and distinctive facets. High interspersion of land facets can promote ecological processes, evolutionary interaction, and range shift. Relevant studies suggest land‐facet diversity is a good surrogate for today's biodiversity, but fails to conserve some species. To minimize such failures, a reserve design based on land facets should complement, rather than replace, other approaches. Designs based on land facets are not biased toward data‐rich areas and can be applied where no maps of land cover exist. 相似文献
315.
《International Journal of Sustainable Engineering》2013,6(6):382-396
AbstractWith the global increasing importance of sustainable development, sustainable supply chain has gained value among both researchers and industrialists in the last decade. Nowadays, industries are facing pressure from government legislation and the global competition in addition to the pressure from their clients to carry out environmentally – conscious actions. Thus, organisations are required to implement actions to enhance their level of both environmental and economic performances. Traditionally, organisations use criteria such as cost, quality and on-time delivery to evaluate their suppliers’ performance. Although there have been numerous studies on the common criteria for these assessments, very few studies have taken sustainable criteria into consideration. Thereupon, this study tries to put forward a complete model for selection and evaluation of the suppliers, considering three criteria for sustainability, thus using the fuzzy group graph theory and matrix approach. It is an innovative approach based on fuzzy logic and group decision-making, which aims to treat lack of certainty in selection and evaluation of suppliers. We will also discuss a case study in the industry to demonstrate the effectiveness of our proposed approach. 相似文献
316.
Effective implementation of occupational safety and health (OSH) legislation based on European Union directives requires promotion of OSH management systems ( OSH MS). To this end, voluntary Polish standards (PN-N-18000) have been adopted, setting forth OSH MS specifications and guidelines. However, the number of enterprises implementing OSH MS has increased slowly, falling short of expectations, which call for a new national policy on OSH MS promotion. To develop a national policy in this area, a survey was conducted in 40 enterprises with OSH MS in place. The survey was aimed at identifying motivational factors underlying OSH MS implementation decisions. Specifically, workers’ and their representatives’ involvement in OSH MS implementation was investigated. The results showed that the level of workers ‘ involvement was relatively low, which may result in a low effectiveness of those systems. The same result also applies to the involvement of workers’ representatives and that of trade unions. 相似文献
317.
Community-level initiatives will play a key role in meeting greenhouse gas reduction targets. This paper examines the experience gained in applying a targeted social marketing approach to foster local-scale community pro-environmental behavioural change in the City of York, UK. This involved determining the neighbourhood carbon footprint, identifying residents that had access to appropriate infrastructure and were receptive to green issues. Six community teams were recruited from the selected neighbourhoods and provided with information, advice and mentoring on how to reduce their carbon footprint over a six-month period. A statistically significant reduction in carbon emissions was achieved. Each participant achieved a mean reduction in their carbon footprint of 2.0 tonnes of CO2e/year. The largest reductions were achieved in the areas of shopping and home energy. In addition, it helped to foster community spirit. Based on the experience gained from implementing this approach, a cost-effective model of community engagement is proposed. 相似文献
318.
煤矿生产中瓦斯事故的发生及其危害程度的不确定性使得定量评价损失很困难.本文提出一种评估煤矿瓦斯事故严重程度和相关安全投资效益的方法.通过分析影响煤矿瓦斯事故发生的主要因素,利用专家调查法推断出瓦斯事故的发生概率和严重程度,进而估计出瓦斯事故的风险度并定量评价相关的安全投资效益.通过这种方法,可以提出各种安全投资方案并进行安全投资效益比较,据此选择安全投资效益最好的安全投资方案进行安全投资决策,最大限度地降低煤矿瓦斯事故的发生概率和危害程度.实例分析表明这种方法是有效的. 相似文献
319.
Athanasios Ragkos Asimakis Psychoudakis Argiro Christofi Alexandros Theodoridis 《Regional Environmental Change》2006,6(4):193-200
This study proposes the valuation of wetland functions as an alternative to the conventional approach to wetland valuation, in order to derive indicators for decision-making in wetland management. It is illustrated that these functions can be valuated in terms of the goods and services they provide to society. Using a functional approach, the functions are identified and the goods and services they provide are explicitly allocated among them; then, the latter are valuated with the Contingent Valuation method. Statistical analysis of the data provides welfare measures that reflect the value of these functions. It is argued that the values of separate functions are more useful in policy-making than their aggregated value.
相似文献
Athanasios RagkosEmail: Phone: +30-2310-998826Fax: +30-2310-998828 |
320.
中国收入差距与环境质量关系的实证检验--基于对环境库兹涅茨曲线的扩展 总被引:11,自引:0,他引:11
在对环境库兹涅茨曲线(EKC)假说扩展的基础上,分析和验证了收入差距与环境质量之间的关系。应用联合国统计司公布的中国1986—2002年度二氧化碳排放总量数据,通过计量模型论证收入差距与环境质量之间的假设。结果发现,收入差距扩大会刺激二氧化碳排放,收入差距越大这种影响的效果就会越恶劣。而且收入差距因素还会通过作用于经济增长,促使经济增长对环境的污染程度加强。延迟转折点的到来。因此,我国目前在促进经济增长的同时,要以提高社会整体福利为目的,缩小居民收入差距,这将有利于环境质量的改善和提高。 相似文献