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881.
The contingent valuation method (CVM) is one of the main methods for evaluating non-market values of resources. It originated
in the United States and was introduced into China during the 1980s and 1990s. However, application of CVM in China is highly
controversial based on three primary aspects: (1) the appropriate guidelines for CVM; (2) the elicitation techniques for willingness
to pay (WTP); and (3) reliability and validity testing of CVM. The major objectives of this paper are to review the recent developments
pertaining to guidelines, elicitation techniques, and reliability and validity testing for application of CVM, and to summarize
the limitations of and measures for improving application of CVM in China. The applicability of CVM in China is discussed
to enhance the future development of CVM in China. 相似文献
882.
论中国城市生态健康与环境污染修复 总被引:1,自引:0,他引:1
从大气污染、水体污染、固体废弃物污染、噪声污染和土壤污染体等方面,对中国城市生态健康面I临的问题和环境污染现状进行了分析研究。结果表明,城市环境污染形势依然严峻,城市生态健康受到严重威胁,日益成为制约城市健康发展的主要因素。在此基础上,提出了中国城市环境污染修复的建议,认为保持生态健康,城市环境污染的物理和化学修复措施结合生物修复,是构成生态修复的重要要素。在实际修复过程中,把物理修复、化学修复和生物修复更好地结合起来,才能形成有效的生态修复技术。应该进一步增强城市生态健康意识,复合的城市生态系统还需用系统、生态的方法对城市环境污染进行修复,以实现可持续发展和构建和谐社会。 相似文献
883.
Dawn Day Biehler 《Geoforum》2009,40(6):1014-1023
This paper traces changes in the political ecology of insects and chemicals in US public housing since Congress founded public housing in 1937. Drawing upon the literature of critical geographies of home, urban political ecology, and medical history, it argues that the constitution of “public” and “private” space within public housing was deeply entangled with pest control practices there. Prior to 1945, reformers treated the housing as a commons, in part compelled by the mobility of bedbugs and the pesticide used to combat them, both of which were seen as serious health threats. Managers were also motivated by social welfare ideologies, while residents eagerly assisted with communal control policies in order to achieve freedom from the health insults of bedbugs. Following 1945, however, new synthetic pesticides like DDT seemed to stay safely within one apartment unit, encouraging housing managers to abandon community-oriented pest control practices. Meanwhile, curtailed budgets, particularly after the Housing Act of 1949, left the infrastructure of public housing to decay, rendering units more physically permeable even as managers neglected the communities there. The new pesticides nearly eradicated bedbugs, but tenacious populations of German cockroaches blossomed thanks to the permeable buildings and synthetic pesticides. Residents grew increasingly resistant to pesticide use as they observed that cockroach populations went unabated. The paper serves as a case for applying political ecology frameworks to domestic spaces, and also argues that housing quality and domestic pesticide use are not merely private responsibilities but should be regarded as environmental justice issues. 相似文献
884.
Based on this preliminary study, existing sand and gravel mining regulations (in Maine, USA) can be inferred to provide some
protection to water resources. Sand and gravel deposits are important natural resources that have dual uses: mining for construction material and pumping for drinking water. How the mining of sand and gravel affects aquifers and change aquifer vulnerability to contamination
is not well documented. Mining regulations vary greatly by state and local jurisdiction. This study test metrics to measure
the effectiveness of mining regulations. The sand and gravel aquifer system studied is covered with former and active gravel
pits to nearly 25% of its areal extent. Data from homeowner interviews and field measurements found scant evidence of changes
in water quantity. Water quality analyses collected from springs, streams, ponds and wells indicate that the aquifer was vulnerable
to contamination by chloride and nitrate. However, water quality changes can not be related directly to mining activities. 相似文献
885.
W. D’Alessandro L. Brusca K. Kyriakopoulos G. Michas G. Papadakis 《Environmental Geology》2009,57(8):1723-1728
Volcanic and geothermal areas are one of the major natural sources of H2S to the atmosphere. Its environmental impact is often the main cause of the opposition to the development of geothermal energy
exploitation programs. In this paper, we analyze the air concentrations and dispersion pattern of naturally emitted H2S at the geothermal area of Sousaki (Corinthia, Greece). Measurements, made with a network of passive samplers, evidence a
rapid decrease of concentration values away from the emission points. The fact that the decrease is more pronounced in the
summer with respect to the winter indicates that it is not only due to a dilution effect, but also to redox reactions favored
by higher temperatures and intense sunlight typical of the summer period. 相似文献
886.
我国东北地区晚更新世中晚期环境变化与猛犸象—披毛犀动物群绝灭研究综述 总被引:2,自引:0,他引:2
通过对文献资料的总结、统计分析,结合对我国东北地区的实地考察和初步研究结果,论述了我国东北地区晚更新世中晚期以来环境变化与猛犸象—披毛犀动物群演化、灭绝的研究现状和存在问题及其与国际对相应时段猛犸象研究之间的差距。提出加强对我国东北地区晚更新世气候环境的重建、认识气候变化的区域特点和突变性,系统而可靠地建立以猛犸象—披毛犀为主的化石动物年代序列、区分主要类型化石动物年代是研究的关键。以独立的气候环境变化和化石动物的年代序列为参照系,在区域环境变化的框架内讨论化石动物群生存的气候环境、生态特征和灭绝过程,进而探讨动物群演化及灭绝与气候环境变化的关系。这将为认识区域环境突变、动植物对环境变化的响应、我国东北地区晚更新世猛犸象—披毛犀动物群与欧亚大陆其它地区猛犸象之间的内在联系,认识人类演化与生存环境的适应、动植物演替与绝灭的临界条件等一系列重大科学问题提供资料。 相似文献
887.
《Geoforum》2017
Mechanisms of democratic participation have been activated in Colombia since 2006 for the purpose of protecting water sources, hydrosocial territories and peasant livelihoods. A chronological perspective on the numerous and varied cases illustrates their cumulative, transformative effect on judicial decisions taken by the high courts, which have endorsed these mechanisms of direct democracy and expanded the scope of democratization to socioenvironmental issues. The process of environmental democratization in Colombia has been gradual, starting with the creation of opportunities for citizen participation in the Constitution of 1991; followed in the first decade of this century by the activation of the mechanisms of democratic participation created; and culminating with the watershed Constitutional Court ruling T-445 of 2016, which confirmed the right of municipalities to consult with their citizens about mining and oil extraction in their territories. The cases are analyzed here through the lens of democratization and transformative and judicialized politics. The paper argues that the reconfiguration of power through the use and contestation of participatory mechanisms reveals an ambiguous state-formation process characterized by repressed democratization. It also demonstrates that the process of environmental democratization that started with the activation of the democratic participation mechanisms introduced in the Constitution of 1991 has been one of transformative democratic politics, in which a dynamic array of political actors have consolidated democratic participation on environmental issues through constitutional lobbying and activism. 相似文献
888.
《Geoforum》2017
This article sets out an agenda for research that (re)connects research on children’s geographies and childhood studies with studies of spatial literacy. Research on children’s environmental cognition and, latterly, spatial literacy, has been artificially and problematically separated from the majority of research in childhood studies. Our fundamental aim in this article is to argue for – and to evidence – greater attention to how spatial literacy and children’s everyday lives are embedded in one another. To support our broader call for a synthetic research agenda, we draw on some more focussed, qualitative empirical material taken from a large-scale project about children’s mobilities and everyday lives in newly-built urban communities. Our analysis focuses upon children’s interpretations of Global Positioning Systems (GPS) tracks of their mobilities, set against a background of Google Earth imagery. In doing so, we showcase one suite of ways in which research on environmental cognition and children’s geographies might proceed together. We demonstrate that children not only displayed analytical skills (for instance, in relation to scaling effects and pattern recognition) but that many also exercised higher-level, critical analysis, especially in relation to errors on Google Earth outputs. Simultaneously, we interrogate the recursive articulation of a range of qualitative indicators of spatial literacy, with children’s everyday mobilities, routines, emotions and memories. The paper analyses how new conceptual languages and technologies being propounded by spatial literacy scholars could afford a more enriched understanding of key contemporary concerns for children’s geographers, and, recursively, what spatial literacy scholars might gain from engaging with (especially qualitative) research prompted by those concerns. 相似文献
889.
Behavior and Environmental Effects of Mercury Relevant to the Melt of Alpine Glacier:A Review 总被引:1,自引:0,他引:1
Mercury (Hg) is a global pollutant. As one of the significant cryospheric environmental matrix, snow-ice plays a unique role in Hg biogeochemical cycling, which has drawn a wide attention of scientists. Besides polar regions, a large aggregate of glaciers are distributed in the high elevation of mid-high latitude areas. These alpine glaciers are proximate to human residence and are sensitive to the climate change, which would readily impact the human society, water resource security and water quality. Consequently, investigating the behavior and environmental effects of Hg relevant to the melt of alpine glaciers represents significant scientific and social importance. The deposition and storage of Hg in alpine glacier areas were outlined and the removal characteristics and transformation of Hg during glacier melt process and transport of Hg in glacier-fed river were summarized. Based on this study, we suggested that glacier be one of the potential sources of Hg to the downstream areas. Moreover, it was worth concerning the fate and environmental effects of Hg in the ecosystem fed by the glacier runoff. Eventually, we proposed prospects of the process of Hg release during glacier melt and the hot issues of Hg transport in glacier runoff. 相似文献
890.
掌握基质吸力对非饱和离子型稀土抗剪强度的影响,对于认清水对矿体强度的弱化作用具有重要意义。现场测试了矿体的土?水特征曲线和抗剪强度,由此得到基质吸力对矿体抗剪强度的影响特性,即随着基质吸力的增大,矿体的内摩擦角略有增大,黏聚力大幅增大。同时,根据进气值所代表的物理意义进行分析可知,当基质吸力小于进气值时,基质吸力对抗剪强度的贡献速率可看成一稳定值;当基质吸力大于进气值时,基质吸力对抗剪强度的贡献速率逐渐减小。由此,以进气值为分界点,提出非饱和强度改进模型,通过改进模型计算得到的抗剪强度贡献值与现场实测值的误差绝对值基本在15%以内,且优于其他模型预测结果,表明本文的非饱和强度改进模型是有效的。 相似文献