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191.
Green Valley, Arizona is a retirement community located near major open-pit copper mines. Mining and milling activities create dust, which degrades air quality, and mine dumps and tailings banks, which degrade the viewscape. Although the tailings banks are highly visible, this study found that consumer surplus lost from dust-polluted air is more than twice that from degradation of viewscape. Consumer surplus lost from both air quality and viewscape degradation is estimated to be between $116,000,000 and $169,000,000. These preliminary estimates are based upon two studies: hedonic property values, and a contingent valuation survey of willingness to pay. 相似文献
192.
Anna Korppoo 《Climate Policy》2003,3(1):67
Russian Kyoto related interests are economic and after the US withdrawal the mission of Russian actors has been to find new demand for Russian credits and allowances. Kyoto related benefits to Russia will be significantly smaller than earlier expected, however, the revenues are now more likely to be focused on climate change mitigation purposes. Competition in the Kyoto market has established buyers’ market and Russia has to accommodate the interests of investors in order to gain benefits. The Russian initiative ‘Green Investment Scheme’ to recycle revenues from International Emissions Trading (IET) to further environmental activities would convene demand for Russian AAUs but experience the same problems than the previous initiatives: inadequate institutional arrangement, unclear division of responsibilities between domestic actors, prolonged ratification process and lack of eligibility strategy. These problems have prevented implementation of GIS so far. Therefore, these problems have to be addressed by high-level Russian policy-makers if serious benefits from Kyoto are sought. Actors building alliances with Russia should focus on assisting with solving these problems. 相似文献
193.
Lucas J. Stal Patrizia Albertano Birgitta Bergman Klaus von Brckel John R. Gallon Paul K. Hayes Kaarina Sivonen Anthony E. Walsby 《Continental Shelf Research》2003,23(17-19):1695
The blooms of cyanobacteria that develop each summer in the Baltic Sea are composed of two functional groups, namely the small-sized picocyanobacteria (Synechococcus sp.) and the larger, colony-forming, filamentous N2-fixing cyanobacteria. The former encompassed both red (phycoerythrin-rich) and blue-green (phycocyanin-rich) species. The majority of the picocyanobacteria measured less than 1 μm and this size fraction comprised as much as 80% of the total cyanobacterial biomass and contributed as much as 50% of the total primary production of a cyanobacterial bloom. The picocyanobacteria are incapable of fixing N2, do not possess gas vesicles and are not toxic. However, a small filamentous Pseudanabaena sp. that could potentially fix N2 was isolated from the picocyanobacteria fraction. The larger cyanobacteria may form surface scums because they possess gas vesicles that make them buoyant. Although their biomass was less than the picocyanobacteria, they therefore form the more conspicuous and nuisance-forming part of the bloom. The larger cyanobacteria were composed mainly of three different species: Nodularia spumigena, Aphanizomenon flos-aquae and Anabaena sp. These all belong to the heterocystous, N2-fixing cyanobacteria. N. spumigena and A. flos-aquae were the dominant species; only N. spumigena was toxic. Although individual Nodularia filaments showed a range of different phenotypes, they all belong to one species as judged from 16S rDNA sequencing. Through determination of the genotypes of many individual Nodularia filaments, it was shown that this population was not clonal and that horizontal exchange of genetic information occurs. N. spumigena and A. flos-aquae were different with respect to their photosynthetic and N2-fixing potentials. Depending on prevailing environmental conditions, these differences would promote the proliferation of one species over the other and hence would determine overall the toxicity of a bloom. Daily integrals of photon irradiance rather than temperature determined the onset of bloom formation. During a bloom, the diazotrophic cyanobacteria fixed N2 at a rate that was 10–20% in excess of their own demand for N. Picocyanobacteria assimilated most of this excess N as shown by 15N incorporation. During bloom conditions, the diazotrophic cyanobacteria met about 50% of the N demand of the total cyanobacterial community. The picocyanobacteria were predominantly N-limited while the diazotrophic cyanobacteria were probably iron limited. These findings allow us to understand the formation of toxic cyanobacterial blooms and also to develop tools to predict bloom formation. 相似文献
194.
Abstract. A series of mudstones corresponding to N.8 to N.17 of Blow from the Uyashinai Mudstone Member, the Onnagawa Formation and the Funakawa Formation in the Taiheizan area of the central Green Tuff region, northeast Japan, was examined by chemical analysis. According to conventional chemical systematics, the mudstones are analyzed in terms of detrital, biogenic-A (siliceous), biogenic-B (calcareous) and hydrogenous components. The relative contribution of the biogenic-A (siliceous) component increases in upward succession in the Uyashinai and Onnagawa mudstones, whereas the contribution of the biogenic-B (calcareous) component is restricted to the lower Uyashinai mudstones. The contribution of hydrogenous components Zn, Pb, Cu and Ba tends to increase during the Nishikurosawa stage, and decreases near the Nishikurosawa/Onnagawa boundary (Pb and Ba) or in the Onnagawa stage (Zn and Cu). The observed enrichment of heavy metals in the Uyashinai mudstones is attributed to the onset of vigorous upwelling of deep water with higher nutrient and metal content associated with a contemporaneous change in global deep-water circulation. 相似文献
195.
Andrea Nightingale 《Geoforum》2003,34(4):525-540
This paper presents a theoretical framework for analyzing human–environment issues that examines shifting, dialectical relationships between social and power relations, cultural beliefs and practices, and ecological processes to allow an interdisciplinary, complex assessment of social and environmental change in Nepal. The purpose of this analysis is to capture the complexity and non-static nature of environmental and social change in the context of uneven development. Drawing from political ecology and feminist geography, this framework brings together scholarship on aspects of human–environment issues that are often pursued in isolation, yet all three processes, social–political relations, cultural practices and ecological conditions, have been acknowledged as important in shaping the trajectory of social and ecological change. I argue that a consideration of the articulations between them is necessary to understand first, how specific land management regimes arise and are dominant over time in specific places. And second, I examine the extent to which these regimes distribute resources equitably within communities, promote economic development and sustain ecological resilience. In this analysis, ecological processes are conceptualised as co-productive of social and cultural processes to explore their role in land management regimes without resorting to environmental determinist or similarly reductive paradigms. I present this framework through the example of natural resource management, specifically community forestry in Nepal, as it offers a rich case study of the relationships between the political economy of land use and the ecological effects of natural resource extraction. 相似文献
196.
徽派建筑的保护已经取得了很大成绩,但仍然存在一些问题。笔者认为,古建筑的保护和地区的经济、社会、文化与生活的发展必须要统筹考虑,可以将徽派建筑设计的理念、技术与现在提倡的绿色建筑设计方法进行对比研究,来考虑如何发展徽派建筑。 相似文献
197.
内陆河流域基于绿水理论的生态—水文过程研究 总被引:1,自引:1,他引:0
水文过程与植物生态过程之间的相互作用,是生态水文学研究的重点。基于Falkenmark等提出的绿水和蓝水概念的生态水文学研究,使水循环与生态学过程紧密地联系起来,并凸现了植物对水循环的作用。按绿、蓝水的理论思路进行分析,植被的水源涵养功能可看作是森林、草地等对天然降水在绿水和蓝水之间的按比例分成;荒漠雨养植被中植物的水循环模式是“纯绿”的,即降雨渗入土壤的水都以蒸散发(绿水)形式消耗掉;荒漠河(湖)岸植物的水循环是由蓝到绿,即其水分来源是地下水(蓝水),经蒸腾(绿水)而消耗。 相似文献
198.
Fiona Nunan Dražen Cepić Bwambale Mbilingi Konstantine Odongkara Ernest Yongo Monica Owili 《社会与自然资源》2018,31(3):306-319
Social ties influence access to knowledge and cooperation in natural resource management, with the sharing of certain characteristics thought to be positive for social cohesion and participatory forms of management. In this article, a holistic characterisation of fisherfolk personal networks is developed, disaggregating results by the main occupational groups within the fisheries studied, to provide a more nuanced understanding of the personal networks of types of fisherfolk. Links are then made between the characteristics of personal networks and evidence on how fisherfolk benefit from their networks, interpreted as contributing to social cohesion within the communities. The personal networks of fisherfolk (boat crew, boat owners and traders/processors) of Kenya, Tanzania and Uganda bordering Lake Victoria were investigated using personal network analysis, with fisherfolk asked who they discuss their fisheries activities with. The analysis found that networks based on the same occupation were more characteristic of fish traders/processors networks than those of boat crew and boat owners and that shared ethnicity, gender and location were characteristic of boat owner and boat crew networks, though shared ethnicity may reflect the composition of the communities rather than choice. Social and economic interactions within the networks were based on provision of credit, social support and advice, suggesting that these form the basis of social cohesion and should be taken into consideration in working with fishing communities in both development interventions and designing collaborative management approaches. 相似文献
199.
Leila M. Harris Danika Kleiber Lucy Rodina Sule Yaylaci Jacqueline Goldin Germaine Owen 《社会与自然资源》2018,31(1):89-105
We analyze the relationship between perceptions of domestic water access, and quality, in relation community engagement. While others have suggested linkages between material conditions of water access and engagement (e.g., that poor water access might spur engagement), to date there have been no studies those test these relationships using statistical methods. Based on a quantitative analysis of survey data from underserved sites in Accra, Ghana, and Cape Town, South Africa, our results show that water access and quality are both predictive of community engagement. The analysis also makes a strong case that there are different dimensions when considering the material conditions of water—in this case, water access and quality each condition engagement in opposite directions. Furthermore, consistent with other studies, our study also shows different demographics (notably gender) mediate these relationships in important ways. 相似文献
200.
西北干旱区生态需水研究 总被引:16,自引:2,他引:14
西北干旱区是水资源稀缺和生态环境相对脆弱的区域。以人类需求为中心的传统水资源开发利用及评价忽视了水资源与生态环境系统之间的关系,引发了众多的生态环境问题。日益恶化的生态环境使得生态需水量受到广泛关注,生态需水量研究由此成为干旱区生态水文学研究新的增长点。文章在综述国内外生态需水研究现状及其面临挑战的基础上,分析西北干旱区水资源转化特点,结合Falkenmark 水资源分类,突出生态需水在水分流中的地位,提出保障生态需水的策略,即:①生态环境稳定性界定;②绿水的保护与高效利用; ③虚拟水战略,旨在为平衡人类需水与自然需水提供重要的理论基础。 相似文献