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941.
针对绿色建筑体系与低碳经济的探讨问题,介绍了什么是绿色建筑,提出了绿色建筑是中国低碳经济建设的必然要求,探讨了绿色建筑的发展,主要包括:国外某些国家绿色建筑的发展和中国绿色建筑的发展,提出了绿色建筑的认识误区,主要包括绿色并不等于高价格和高成本、绿色建筑不仅局限于新建建筑和建筑节能不只是政府的职责,总结出中国绿色建筑的推广与运用,主要是研究和推广符合中国国情的绿色建筑、大力推广“绿色建筑”的标识和中国绿色建筑推广的实例.  相似文献   
942.
Abstract: Conservation biology has provided wildlife managers with a wealth of concepts and tools for use in conservation planning; among them is the surrogate species concept. Over the past 20 years, a growing body of empirical literature has demonstrated the limited effectiveness of surrogates as management tools, unless it is first established that the target species and surrogate will respond similarly to a given set of environmental conditions. Wildlife managers and policy makers have adopted the surrogate species concept, reflecting the limited information available on most species at risk of extirpation or extinction and constraints on resources available to support conservation efforts. We examined the use of surrogate species, in the form of cross‐taxon response‐indicator species (that is, one species from which data are used to guide management planning for another, distinct species) in the Sacramento‐San Joaquin Delta, California (U.S.A.). In that system there has been increasing reliance on surrogates in conservation planning for species listed under federal or state endangered species acts, although the agencies applying the surrogate species concept did not first validate that the surrogate and target species respond similarly to relevant environmental conditions. During the same period, conservation biologists demonstrated that the surrogate concept is generally unsupported by ecological theory and empirical evidence. Recently developed validation procedures may allow for the productive use of surrogates in conservation planning, but, used without validation, the surrogate species concept is not a reliable planning tool.  相似文献   
943.
We measured the concentrations and depth distribution (0-10, 10-20 cm) of 31 PAHs and 12 OPAHs in soils at eleven equidistant sampling points along a 20-km transect in the Angren industrial region (coal mine, power plant, rubber factory, gold mine), Uzbekistan to gain an insight into their concentrations, sources, and fate. Concentrations of all compounds were mostly much higher in the 0-10 cm than in the 10-20 cm layer except in disturbed soil close to the coal mine. Proximity to one of the industrial emitters was the main determinant of PAH and OPAH concentrations. The ∑31PAHs concentrations correlated positively with the ∑7 carbonyl-OPAH (r = 0.98, p < 0.01), ∑5 hydroxyl-OPAH (r = 0.72, p < 0.05), and with industrially emitted trace metals in the topsoil, identifying industrial emissions as their common source. Concentrations of several OPAHs were higher than their parent PAHs, but their vertical distribution in soil suggested only little higher mobility of OPAHs than their corresponding parent PAHs.  相似文献   
944.
张天序 《环境与发展》2020,(2):29-29,31
作为新型绿色环保可降解缓蚀阻垢剂的聚环氧琥珀酸,在包括工业生产在内的诸多领域,均得到了广泛应用,所取得效果也十分突出。本文首先简单介绍了PESA的含义和特点,随后从实际出发,围绕其在钢厂中的具体应用展开了讨论,内容涉及应用试验、效果分析等方面,希望能够为相关人员提供一定帮助。  相似文献   
945.
Parks, waterways, and vegetation enhance the well-being of urbanites and thus warrant consideration in planning and policy-making. It is, however, difficult to assess how land-use change may impact these features and how this in turn may impact well-being. I use a case-study approach to present a framework that combines geospatial and economic valuation techniques to generate indicators of the effects of land-use policies that alter these amenities on community well-being. This framework quantifies the impacts of land-use change on urban environmental amenities in a way that could help communities plan land use so as to maintain well-being as they urbanise.  相似文献   
946.
There is now an emerging sense of the scope and nature of response that can be implemented at building and neighbourhood scales to help adapt cities and urban areas to the changing climate. In comparison, the role of larger natural and semi-natural landscapes that surround and permeate cities is less well understood. Addressing this knowledge gap, this paper outlines two case studies that describe and map the flood risk management functions offered by green infrastructure landscapes situated within the Urban Mersey Basin in North West England. The case studies establish that areas potentially exposed to flooding can be located at some distance, and within different jurisdictions, from upstream areas where the flood hazard may be generated and could be moderated via functions provided by green infrastructure landscapes. This raises planning and governance challenges connected to supporting and enhancing flood risk management functions provided by green infrastructure landscapes.  相似文献   
947.
A city's spatial footprint is covered by extensive impervious building roofs and paved surfaces, which contribute to greater storm-water runoff, more surface pollutants, and less carbon sequestration, hence, worse ecosystem services. This research conducts an empirical study on the ecological and economic impacts of a citywide adoption of green roofs and permeable pavements in Corvallis, OR. The effects on ecosystem services of using green roofs and pervious pavements for a low impact development are modelled using Integrated Value of Ecosystem Services Trade-offs and compared to those from the City's current conventional development without green roofs and pervious pavements. The differences are analysed for ecological impact by storm-water yield, storm-water purification, and carbon sequestration and economic impact by a cost-benefit comparison. The results indicate that low impact development, especially intensive green roofs on commercial/industrial buildings and permeable pavements for parking lots, plays a significant role, even with a higher initial implementation cost, for long-term urban sustainability.  相似文献   
948.
Eremosparton songoricum (Fabaceae) is a rare, native, clonal small shrub of the deserts of central Asia. Although human activities have greatly fragmented the distribution of E. songoricum, it occurs in areas where artificial sand fixing (AS) has been implemented. We sought to explore whether AS promotes survival and growth of E. songoricum. In the Gurbantunggut Desert of northwestern China in June 2010, we established 10 plots in an area where sand fixing occurred (5–10 years previously) and 11 plots on original sand substrate on which some plants had settled without fixing sand. Sand fixing changed soil properties and biological characteristics in sand‐fixed plots. The soil surface where sand fixing occurred was covered by algal crusts and some lichen, but not bare sand (BS). Soil nutrients; water content of deep soil (30–150 cm); overall plant and herbaceous species richness, diversity, abundance, and cover; above‐ and belowground biomass; and cover, biomass, and height of E. songoricum in the sand‐fixed plots were significantly greater than in plots of BS. However, distribution of E. songoricum individuals in the 2 types of plots did not differ. Our results indicate AS may enhance survival of E. songoricum and increase the overall diversity and stability of the desert plant community. We suggest AS as a way to protect this rare desert plant in situ. Efectos de la Fijación Artificial de Arena sobre las Características de la Comunidad de un Arbusto Desértico Raro  相似文献   
949.
The aim of this study was to investigate the similarities and dissimilarities between the pesticide samples in form of emulsifiable concentrates (EC) formulation containing chlorpyrifos as active ingredient coming from different sources (i.e., shops and wholesales) and also belonging to various series. The results obtained by the Headspace Gas Chromatography–Mass Spectrometry method and also some selected physicochemical properties of examined pesticides including pH, density, stability, active ingredient and water content in pesticides tested were compared using two chemometric methods. Applicability of simple cluster analysis and also principal component analysis of obtained data in differentiation of examined plant protection products coming from different sources was confirmed. It would be advantageous in the routine control of originality and also in the detection of counterfeit pesticides, respectively, among commercially available pesticides containing chlorpyrifos as an active ingredient.  相似文献   
950.
文章选用凡尔赛营养液作为基础培养液,分别加入一种含钛植物生长促进剂和TiCl4溶液,以早熟五号大白菜为试验对象,基础培养液作为对照,考察钛元素对大白菜生长的影响及与其他营养元素之间的关系。结果表明:施加含有相同含钛量的植物生长促进剂与TiCl4溶液的大白菜中单株大白菜鲜重增幅分别为35.4%和23.1%;可溶性糖含量增幅为162.5%及118.8%;大白菜中硝酸盐含量的降低幅度分别为15.2%和13.8%;亚硝酸盐含量的降低幅度分别为36.4%和33.8%。同时,还测量了其他相关指标如株高、叶面积、叶绿素含量等。添加TiCl4的培养液与对照相比,在各项指标中都表现出优势,与添加植物生长促进剂的培养液相比,叶绿素、硝酸盐等指标相差不明显。  相似文献   
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