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71.
在对大连市凌水地区实施集中供热前后的环境效益进行定性分析比较的基础上,应用环境经济学的费用效益分析方法,对集中供热的环境效益进行了效益定量化估算,结果表明:实行区域集中供热联片取暖10年后投资费效比为1∶3.3。 相似文献
72.
On the influence of faulting on small-scale soil-gas radon variability: a case study in the Iberian Uranium Province 总被引:2,自引:0,他引:2
In order to evaluate the influence of faulting on the variability of geogenic radon at detailed scale (1:2000), data on gamma ray fluxes, U and Th concentrations in rocks, radon in soil-gas and radon in groundwater were collected in three target areas on the Oliveira do Hospital region (Central Portugal). This region stands on the Iberian Uranium Province, and is dominantly composed of Hercynian granites and metasedimentary rocks of pre-Ordovician age, crosscut by faults with dominant strike N35°E, N55°E and N75°E. Radiometric anomalies are frequent, associated with faults of the referred systems and metasedimentary enclaves; the analytical data confirms that these anomalies are produced by local high uranium contents in rocks and fault-filling materials (n = 34, range 13-724 ppm), while other radiogenic elements are relatively constant (e.g. Th 4-30 ppm). Radon concentration in soil can be extremely high, up to 12,850 kBq m−3 (n = 215), with a large proportion of results above 100 kBq m−3. Unsurprisingly, groundwater also shows high radon concentrations, with observed values in the range 150-4850 Bq.L−1 (n = 17). From the results it is concluded that metasedimentary enclaves, as well as faults, can accumulate uranium from circulating fluids, and as a consequence, strongly locally enhance geogenic radon potential. Due to this fact, for the purpose of land use planning in such uranium-enriched regions, very detailed geological mapping is needed to precisely recognize radon high risk areas. A correlation between radon concentration in soil or in groundwater and gamma ray fluxes was established pointing to the possible use of these fluxes as a first step in assessing geogenic radon potential, at least to geological setting similar to the study area. 相似文献
73.
本文介绍了碳金融的定义以及中国构建完善碳金融体系的背景,指出我国的CDM市场虽然是全球最大的CDM市场,但碳金融还处于起步阶段,缺乏国际CERs定价权,CDM项目存在巨大的风险,这些问题亟需解决。中国的银行业作为中国金融机构的主要组成部分,在构建完善的碳金融市场上起到了十分关键的作用。分析了目前中国银行业参与碳金融的现状及存在的问题,提出了中央银行和中国商业银行介入碳金融的方法。中央银行应与商业银行相互配合使中国的碳金融市场尽快发展和完善。 相似文献
74.
建设秦岭国家中央公园的探究 总被引:1,自引:0,他引:1
通过对秦岭的综合分析,借鉴国外"国家公园"的建设经验,从秦岭目前开发现状存在的问题及其原因进行分析研究,提出应成立国家秦岭管理局,科学开发保护秦岭,分不同区域建设秦岭国家中央公园;在发展生态旅游的同时,积极整合资源,争取加入世界人与生物圈,联合申遗,推动秦岭走向世界,从而实现秦岭地区人与自然的可持续发展。 相似文献
75.
Luis A. Caballero Alon Rimmer Zachary M. Easton Tammo S. Steenhuis 《Journal of the American Water Resources Association》2012,48(5):1022-1031
Caballero, Luis A., Alon Rimmer, Zachary M. Easton, and Tammo S. Steenhuis, 2012. Rainfall Runoff Relationships for a Cloud Forest Watershed in Central America: Implications for Water Resource Engineering. Journal of the American Water Resources Association (JAWRA) 48(5): 1022‐1031. DOI: 10.1111/j.1752‐1688.2012.00668.x Abstract: Understanding the basic relationships between rainfall and runoff is vital for effective management and utilization of scarce water resources. Especially, this is important in Central America with widespread potable water shortage during the dry months of the monsoon. Potential good water sources are cloud forests, but little information concerning its potential is available to water supply engineers. Our objective is to define rainfall‐runoff‐base flow relationships for a cloud forest catchment. Flumes were installed for measuring river flow in four subwatersheds in La Tigra National Park, Honduras. One of the four watersheds was a 636‐ha subwatershed (WS1) with 60% cloud forest coverage. Precipitation averaged 1,130 mm/yr over the entire basin. About half of the total rainfall became runoff for the cloud forest watershed whereas, for the adjacent undisturbed forested watershed, the total discharge was <20% of the amount of precipitation. Infiltration rates were generally greater than rainfall rates. Therefore, most rainfall infiltrated into the soil, especially in the upper, steep, and well‐drained portions of the watershed. Direct runoff was generated from saturated areas near the river and exposed bedrock. This research provides compelling evidence that base flow is the primary contributor to streamflow during both wet and dry seasons in cloud forest catchments. Protecting these flow processes over time is critical for the sustained provision of potable water. 相似文献
76.
研究以能源消费模式为切入点,分析中原经济区能源消费总量、消费结构和利用效率的现状水平,并分析能源消费引起的大气环境压力状况。基于经济发展速度调控及节能减排力度的不同,设置2020年三种能源消费情景,使用区域能源消费总量优化模型模拟预测不同情景下的能源消费总量,并分析不同情景下的大气环境压力。结果表明,快速发展和适度发展Ⅰ情景下,2020年区域能源消费总量将比2012年增加4.2×10~8tce和2.4×10~8tce,煤炭消费总量将增加3.1×10~8tce和1.2×10~8tce,大气污染物排放压力增加30%和50%;适度发展Ⅱ情景下,能源消费总量将增加0.2×10~8tce,煤炭消费总量将下降0.3×10~8tce,大气污染物排放压力将降低20%。因此,要实现经济发展稳步增长(年均增长率7.7%)和大气污染物排放总量削减10%目标,重中之重是实现煤炭消费总量"零增长"或"负增长",同时力争能源消费总量控制在5×10~8~6×10~8tce,凭借煤炭占比大幅下降(降至65%左右)最大限度发挥能源供给领域节能效应,依靠产业结构升级节能效应和技术节能拓展能源消费领域节能空间,将能效水平提高至0.6tce/万元以下。 相似文献
77.
Fabrizio Frascaroli Shonil Bhagwat Riccardo Guarino Alessandro Chiarucci Bernhard Schmid 《Ambio》2016,45(4):468-479
Sacred natural sites (SNS) are instances of biocultural landscapes protected for spiritual motives. These sites frequently host important biological values in areas of Asia and Africa, where traditional resource management is still upheld by local communities. In contrast, the biodiversity value of SNS has hardly been quantitatively tested in Western contexts, where customs and traditions have relatively lost importance due to modernization and secularization. To assess whether SNS in Western contexts retain value for biodiversity, we studied plant species composition at 30 SNS in Central Italy and compared them with a paired set of similar but not sacred reference sites. We demonstrate that SNS are important for conserving stands of large trees and habitat heterogeneity across different land-cover types. Further, SNS harbor higher plant species richness and a more valuable plant species pool, and significantly contribute to diversity at the landscape scale. We suggest that these patterns are related not only to pre-existent features, but also to traditional management. Conservation of SNS should take into account these specificities, and their cultural as well as biological values, by supporting the continuation of traditional management practices.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-015-0738-5) contains supplementary material, which is available to authorized users. 相似文献78.
ke Berg 《Agriculture, ecosystems & environment》2002,90(3):587
Plantations of short-rotation coppice (SRC) have a potential for being a useful measure to stop the ongoing impoverishment of farmland biodiversity by increasing structural diversity, and decreasing cultivation intensity and use of pesticides in intensively managed farmland landscapes. The aim of this study was to investigate the relative importance of the structure of the plantation and composition of adjacent habitats for breeding birds in 41 SRCs (meansize±S.E.=9.4±1.6 ha). Mean number of species per ha in the SRCs was 2.8±0.3 species and there were more farmland birds (32 species, 808 territories) than forest birds (22 species, 400 territories). A major result of the present study was the strong influence of adjacent habitats on bird community composition (18 of 22 analysed species affected). There were large differences in bird communities between forest-bordered and open-bordered sites, but occurrence of residual habitats (i.e. other habitats than forest, pastures, shrub areas and arable fields) was also associated with occurrence of several species. The second factor of major importance for the bird fauna was the height of the plantations. Most species (14) were associated with tall plantations (>2 m), seven species were associated with plantations of intermediate (1–2 m) height, and six species were associated with plantations of low height (<1 m). A comparison of ecological traits between species classified as preferring SRC and species classified as avoiding SRC suggests that nest height was the only ecological character associated with a preference for Salix habitats, i.e. species with nests on the ground or in shrubs were more abundant in Salix habitats than in farmland landscapes in general. However, a broad spectrum of species was found in the SRCs and many of these seemed to be dependent on habitat features outside the plantations. Planting of Salix in intensively managed farmland plains will have positive effects on bird diversity by increasing the structural diversity of the landscape. In contrast, plantations on infields in forest-dominated landscapes will have negative effects, since the mosaic structure (i.e. mixture of open and forested habitats) positive for most farmland birds will disappear, and Salix plantations favour relatively few forest species. Additionally, Salix could be planted along sharp edges between coniferous plantations and open farmland in order to increase the complexity of the ecotone in intensively managed forest-farmland landscapes. 相似文献
79.
Franois Laurent Wolfram Anker Didier Graillot 《Journal of the American Water Resources Association》1998,34(1):123-134
ABSTRACT: A method for water resources protection based on spatial variability of vulnerability is proposed. The vulnerability of a water resource is defined as the risk that the resource will become contaminated if a pollutant is placed on the surface at one point as compared to another. A spatial modelling method is defined in this paper to estimate a travel time between any point of a catchment and a resource (river or well). This method is based on spatial analysis tools integrated in Geographical Information Systems (GIS). The method is illustrated by an application to an area of Massif Central (France) where three different types of flow appear: surface flow, shallow subsurface flow, and permanent ground water flow (baseflow). The proposed method gives results similar to classical methods of estimation of travel time. The contribution of GIS is to improve the mapping of vulnerability by taking the spatial variability of physical phenomena into account. 相似文献
80.
Despite the fact that all successful, documented cases of industrial symbiosis to this day have been self-organizing, some authors and development officials have suggested that increased public planning might deliver better results in this respect than spontaneously evolved market coordination. This paper takes an historical approach to suggest that comprehensive planning is unlikely to live up to the expectations of its proponents.The essay is structured as follows. The first section provides short case studies of industrial symbiosis in highly different economic and institutional settings, the essentially free-market regime of Victorian England and communist Hungary (1948–1989). The available evidence suggests that market coordination proved much more favorable to the emergence of industrial symbiosis, despite the elaboration of a comprehensive policy to that effect in Hungary. Insights derived from the so-called “Austrian” critique of central planning are then used to explain this paradox. The analysis presented suggests that the Hungarian planners’ failure was not so much the result of the bad implementation of sound policies, but the logical outcome of a top-down approach’s shortcomings. Policy implications for the public planning of industrial symbiosis in a mixed economy are then derived and the case for self-organization is found more compelling. The creation of more innovative institutions that will force firms to “internalize their externalities” while leaving them the necessary freedom to innovate is viewed as an urgently needed and promising path towards increased, sustainable reuse of industrial by-products. 相似文献