西安市2013年PM_(2.5)浓度变化分析研究

全面分析2013年西安市13个国控环境空气质量自动监测子站PM2.5监测数据。结果表明:2013年西安市环境空气中PM2.5年均值为105μg/m3,超过《环境空气质量标准》(GB 3095—2012)二级要求(35μg/m3)200.0%,污染较严重;西安市各子站PM2.5月均值总体呈两边高、中间低的"V"型趋势,全市及各子站PM2.5月均值分别为44~206、32~275μg/m3;采暖期(上半年采暖期为1—3月,下半年采暖期为11—12月)、非采暖期(4—10月)PM2.5平均值分别为156、70μg/m3;上、下半年采暖期PM2.5平均值分别为178、124μg/m3;西安市气象风力以微风为主,雨天集中在5—9月,期间PM2.5月均值小于80μg/m3。     

Testing The Pearl Hypothesis: Natural resources and trust

Do natural resources reduce social trust? This paper reviews the literature on natural resources and on trust. The existing theoretical and empirical literature suggests that natural resources can reduce trust through several indirect mechanisms. Notably, studies show that natural resources lead to institutional degradation, corruption, inequality, and civil war, all of which have been associated with reduced trust. In addition, game theoretical work on windfall gains suggests that there may be direct effect of natural resources on trust. This paper tests empirically whether there is a direct effect of natural resources on trust (The Pearl Hypothesis), using cross-country data. The results indicate that no such direct effect exists, but we find a significant effect on trust of intermediate variables affected by natural resources, such as institutions, corruption, inequality and/or civil war. Importantly, the relationship between corruption and trust turns out to be non-linear, indicating that the effect of natural resources on trust depends on the initial corruption level of a country. In highly corrupt societies, institutional improvements that reduce corruption may also undermine trust, which poses difficult challenges for anti-corruption policy.     

A theoretical overview of the relationship between the resource curse and genuine savings as an indicator for “weak” sustainability

This paper shows the strong relation between the factors that lead to the resource curse (RC) and factors that lead to a decline of genuine savings (GS). There is substantial empirical evidence that economies that rely predominantly on their natural resources are also characterized by slower economic growth. This so‐called RC is commonly traced back to the fact that natural resources' generate rents that are independent of a country's economic performance, which can lead to suboptimal reinvestments of this consumed natural capital. We argue that the factors responsible for the RC also have a negative effect on GS, a concept that measures “weak” sustainable development by considering reinvestment of natural capital rents in physical and human capital. We discuss whether the RC hampers possibilities for resource abundant countries to obtain sufficiently high rates of GS, and find indeed many reasons why resource‐dependent countries have problems achieving positive GS rates. We survey both areas of research, emphasizing the influence of the exogenous and endogenous determinants of economic growth, which are usually used to theoretically and empirically explain the RC on the three different forms of capital considered by GS. We specify why most countries suffering from the RC have negative GS rates and explain in detail where the linkages are. This overview could help with potential advancements in the explanation of GS through the inclusion of RC effects.     

江苏省地理标志概况与价值评估体系构建研究

以江苏省43个地理标志为研究对象,根据国家地理标志的分类方法对其进行分类,构建价值评估体系,探讨地理标志产品的内在价值及发展重点。研究表明,江苏省地理标志类型较为单一,分布均匀;开发程度不同,可分为开发匮乏型、有待开发型和开发成熟型。通过价值体系评价可见,江苏省应重点挖掘产品的自身特色,发展价值意义突出的地理标志。     

张家界溶洞旅游资源价值评价与开发研究

溶洞是重要的旅游资源,开发得当可获得良好经济效益,否则便会造成不可逆的资源破坏。以张家界溶洞资源为研究对象,在对溶洞资源基本情况进行调查的基础上,对溶洞的景观价值进行定量评价,并提出溶洞开发措施,为张家界市溶洞旅游的可持续开发利用提供理论依据。     

CFD分析在烟气脱硫中的实际运用与研究

为降低某公司烧结机干法脱硫装置烟道阻力,减少引风机出力,实现节能优化,运用计算流体力学软件,对引风机出口烟道内流场进行三维数值模拟,并根据分析结果进行烟道的优化改造。改造后,吸收塔入口负压由-200Pa提升至-560Pa,风机电流由328A降为301.4A,节能降耗显著。     

A Socio-Ecological Assessment Aiming at Improved Forest Resource Management and Sustainable Ecotourism Development in the Mangroves of Tanbi Wetland National Park, The Gambia, West Africa

Although mangroves dominated by Avicennia germinans and Rhizophora mangle are extending over 6000 ha in the Tanbi Wetland National Park (TWNP) (The Gambia), their importance for local populations (both peri-urban and urban) is not well documented. For the first time, this study evaluates the different mangrove resources in and around Banjul (i.e., timber, non-timber, edible, and ethnomedicinal products) and their utilization patterns, including the possibility of ecotourism development. The questionnaire-based results have indicated that more than 80% of peri-urban population rely on mangroves for timber and non-timber products and consider them as very important for their livelihoods. However, at the same time, urban households demonstrate limited knowledge on mangrove species and their ecological/economic benefits. Among others, fishing (including the oyster—Crassostrea cf. gasar collection) and tourism are the major income-generating activities found in the TWNP. The age-old practices of agriculture in some parts of the TWNP are due to scarcity of land available for agriculture, increased family size, and alternative sources of income. The recent focus on ecotourism (i.e., boardwalk construction inside the mangroves near Banjul city) received a positive response from the local stakeholders (i.e., users, government, and non-government organizations), with their appropriate roles in sharing the revenue, rights, and responsibilities of this project. Though the guidelines for conservation and management of the TWNP seem to be compatible, the harmony between local people and sustainable resource utilization should be ascertained.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-012-0248-7) contains supplementary material, which is available to authorized users.     

环境健康价值评估中的年龄效应研究

在环境健康价值评估研究中,统计寿命价值和年龄之间的关系是理论和实证研究焦点之一,也是重要的学术问题。长久以来,环境政策效益评估中是否应该赋予老年人较低的统计寿命价值一直存在广泛争议,且尚未得到一致性结论。通过设计选择实验,对北京市空气质量改善的健康效益进行了抽样调查,并采用MNL模型对北京市约500个居民的调查数据进行回归分析,估算了不同年龄人群对健康风险减少的支付意愿,针对中国人群中统计寿命价值和年龄之间的关系进行实证探讨。结果表明:一方面,在总体样本中设置年龄虚拟变量,回归结果表明年龄变量系数的符号均显著为负,即年龄因素对减少空气污染带来的死亡风险降低的支付意愿具有显著的影响,年龄越大支付意愿相对越小;另一方面,不同年龄人群分组样本结果显示,统计寿命价值与年龄之间呈现"倒U型"关系,统计寿命价值在中国存在"老年折扣"现象。研究结果可为我国环境政策的健康效益分析中如何考虑年龄的影响提供重要依据。     

pH对煤泥水絮凝沉降的影响

选择聚合氯化铝(PAC)/阴离子型聚丙烯酰胺(PHP)、氯化钙(CaCl2)/非离子型聚丙烯酰胺(NPAM)组合与NPAM、PHP、两性离子型聚丙烯酰胺(ZPAM)作为絮凝剂,在对道清选煤厂水采筛下原生煤泥和浮选尾矿的煤泥水进行组合药剂絮凝实验的基础上,考察了pH对煤泥水絮凝沉降的影响。实验结果表明,在不同的pH下,煤泥水的絮凝效果不同:在酸性条件下,宜单独使用有机高分子絮凝剂;在中性至碱性条件下,无机凝聚剂和有机絮凝剂联合使用效果较好。     

Impacts of Surface Gold Mining on Land Use Systems in Western Ghana

Land use conflicts are becoming increasingly apparent from local to global scales. Surface gold mining is an extreme source of such a conflict, but mining impacts on local livelihoods often remain unclear. Our goal here was to assess land cover change due to gold surface mining in Western Ghana, one of the world’s leading gold mining regions, and to study how these changes affected land use systems. We used Landsat satellite images from 1986–2002 to map land cover change and field interviews with farmers to understand the livelihood implications of mining-related land cover change. Our results showed that surface mining resulted in deforestation (58%), a substantial loss of farmland (45%) within mining concessions, and widespread spill-over effects as relocated farmers expand farmland into forests. This points to rapidly eroding livelihood foundations, suggesting that the environmental and social costs of Ghana’s gold boom may be much higher than previously thought.