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231.
Abstract:  Without robust and unbiased systems for monitoring, changes in natural systems will remain enigmatic for policy makers, leaving them without a clear idea of the consequences of any environmental policies they might adopt. Generally, biodiversity-monitoring activities are not integrated or evaluated across any large geographic region. The EuMon project conducted the first large-scale evaluation of monitoring practices in Europe through an on-line questionnaire and is reporting on the results of this survey. In September 2007 the EuMon project had documented 395 monitoring schemes for species, which represents a total annual cost of about €4 million, involving more than 46,000 persons devoting over 148,000 person-days/year to biodiversity-monitoring activities. Here we focused on the analysis of variations of monitoring practices across a set of taxonomic groups (birds, amphibians and reptiles, mammals, butterflies, plants, and other insects) and across 5 European countries (France, Germany, Hungary, Lithuania, and Poland). Our results suggest that the overall sampling effort of a scheme is linked with the proportion of volunteers involved in that scheme. Because precision is a function of the number of monitored sites and the number of sites is maximized by volunteer involvement, our results do not support the common belief that volunteer-based schemes are too noisy to be informative. Just the opposite, we believe volunteer-based schemes provide relatively reliable data, with state-of-the-art survey designs or data-analysis methods, and consequently can yield unbiased results. Quality of data collected by volunteers is more likely determined by survey design, analytical methodology, and communication skills within the schemes rather than by volunteer involvement per se.  相似文献   
232.
本文通过对不同阶段工程造价内容的分析,详细论述了有效控制工程造价的必要性以及进行工程造价控制的方法。  相似文献   
233.
Marine-protected areas (MPAs) are vital to marine conservation, but their coverage and distribution is insufficient to address declines in global biodiversity and fisheries. In response, many countries have committed through the Aichi Target 11 of the Convention on Biological Diversity to conserve 10% of the marine environment through ecologically representative and equitably managed MPAs by 2020. The rush to fulfill this commitment has raised concerns on how increasing MPA coverage will affect other elements of Target 11, including representation and equity. We examined a Philippines case study to assess and compare 3 MPA planning approaches for biodiversity representation and equitable distribution of costs to small-scale fishers. In the opportunistic approach, MPAs were identified and supported by coastal communities. The donor-assisted approach used local knowledge to select MPAs through a national-scale and donor-assisted conservation project. The systematic conservation planning approach identified MPA locations with the spatial prioritization software Marxan with Zones to achieve biodiversity objectives with minimal costs to fishers. We collected spatial data on biodiversity and fisheries features and performed a gap analysis to evaluate MPAs derived from different approaches. We assessed representation based on the proportion of biodiversity features conserved in MPAs and distribution equity by the distribution of opportunity costs (fishing areas lost in MPAs) among fisher stakeholder groups. The opportunistic approach did not ineffectively represent biodiversity and resulted in inequitable costs to fishers. The donor-assisted approach affected fishers disproportionately but provided near-optimal regional representation. Only the systematic approach achieved all representation targets with minimal and equitable costs to fishers. Our results demonstrate the utility of systematic conservation planning to address key elements of Target 11 and highlight opportunities (e.g., integration of local and scientific knowledge can address representation and equity concerns) and pitfalls (e.g., insufficient stakeholder considerations can exacerbate social inequalities) for planning MPAs in similar contexts.  相似文献   
234.
Weather anomalies have a range of adverse contemporaneous impacts on health and socio-economic outcomes. This paper tests if temperature anomalies around the time of birth can have long-term impacts on individuals' economic productivity. Using unique data sets on historical weather and earnings, place and date of birth of all 1.5 million formal employees in Ecuador, we find that individuals who have experienced in-utero temperatures that are 1 °C above average are less educated and earn about 0.7% less as adults. Results are robust to alternative specifications and falsification tests and suggest that warming may have already caused adverse long-term economic impacts.  相似文献   
235.
The article quantifies the size of ‘hidden’ social costs that are incurred by forestry offsets in the voluntary market that promise to offset present emissions sometime in the future. It does this by estimating the difference between the social costs of carbon (C) emitted and of costs offset by removal of C from the atmosphere by reforestation/afforestation. All current attempts to make forestry offsets more reliable focus on quality control rather than the mismatch of the timing of emissions and their offset. Recommendations that follow from the analysis are twofold. First, that markets for carbon dioxide equivalent (CO2e) removals by voluntary offsets should be confined to the annual incremental removals actually achieved. Second, the promoters of voluntary offsets projects should declare the annual stream of carbon credits and debits expected so that buyers can place a present value on such projects.  相似文献   
236.
人力资本综合存量的度量方法有采用产出法分析,也有用投入法来分析;有从理论上推理,也有从经验数据上论证。分析方法有从教育人力资本角度出发,也有从健康人力资本角度出发。而绝大多数文献很少将教育和健康因素同时纳入考虑,仅分析其中一个方面无疑会带来测量的误差。若能同时考虑教育和健康,由新的度量方法产生新数据,由此带来新结论或是能对已有结论作进一步地论证,则是对以往文献研究的一个补充。因此,本文从四个维度建立新型人力资本综合测量体系,通过因子分析法对人力资本的综合水平进行了衡量。其中四个维度主要是指教育、劳动力再培训、身心健康和劳动力合理流动。在此基础上,把人力资本综合存量这一指标引入Solow模型中,构建扩展的Solow模型。利用扩展Solow模型,并结合最新人口统计数据进行实证分析,建立扩展的中国经济增长模型。研究发现人力资本和技术进步正逐渐成为我国经济增长的主要影响因素,劳动力数量对经济增长的影响在逐渐减弱。在我国经济发展的新阶段,如何在控制人口数量和提高经济发展水平方面协调各项工作成为当前的热点问题。为此我们针对教育投入,全民人口素质,中高端人才培养,经济增长方式创新等方面提出一些建议。  相似文献   
237.
238.
ABSTRACT

This study examines a community garden in Copenhagen, Denmark, "The Urban Integration Gardens" that endeavours to strengthen social integration in the local multicultural neighbourhood. The "community" in the gardens is explored, with a focus on how they foster social capital, particularly opportunities for "bridging" social capital. A mixed-methods approach is used, by employing a qualitative analysis of gardeners’ perceptions of "community", diversity and inclusivity, through the lens of "cognitive" social capital, and the meanings the gardeners assign to their experiences, and how they understand their involvement in the gardens. We also examine "structural" dimensions of social capital, involving quantitative data from a questionnaire and data from Statistics Denmark, comparing data concerning socio-demographic backgrounds from gardeners and residents in the local neighbourhood and Copenhagen. Major findings include that the garden generates both bonding and bridging "cognitive" social capital, and the gardeners consistently agreed that the garden has a strong community, and is permeated by diversity and inclusivity. Nonetheless, data from Denmark’s Statistics Office reveal that the garden does not "represent" the diversity in the neighbourhood regarding the distribution of members with a Western/non-Western background, as well as social class. This suggests that endeavours to involve co-citizens with non-Western backgrounds and gardeners with lower social status are restrained by potential structural barriers, which limits the "width" of bridging social capital in the garden.  相似文献   
239.
赫尔曼·戴利及其生态经济理论评述   总被引:1,自引:0,他引:1  
赫尔曼.E.戴利是美国著名的生态经济学家,对主流经济增长理论的尖锐批评而闻名于学术界。在批判主流经济增长理论的基础上,戴利形成了自己独具特色的生态经济思想。他的理论贡献主要包括可持续发展、宏观环境经济学和稳态经济等几个方面。  相似文献   
240.
This paper aims to practically contribute to the literature on the use of cost–benefit analysis (CBA) and economic evaluation in environmental decision-making through a practical case study: the implementation of the Water Framework Directive (WFD) in France, for the first cycle (2010–2015). The WFD requires that Member States achieve “good status” for all water bodies in 2015. However, exemptions can apply, if justified, on natural, technical or economic reasons. For the latter, EU guidance documents recommend to use CBA. In France, the water agencies carried out 710 CBAs on proposed restoration projects for water bodies. This article reports on this experience. Issues concerning these analyses are discussed, especially the assessment of non-market benefits. Finally, this article questions the use of economic analysis in the implementation of environmental policy.  相似文献   
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