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131.
排污权交易是利用市场机制控制环境污染的有效途径。明确排污权的产权性质无论是对生产者还是对管理者都具有十分重要的意义。本论文将对排污权的产权性质和内涵进行分析。  相似文献   
132.
Silicon carbide (SiC) heating elements (siliconits) are widely used at high-temperature fields. The raw materials, manufacture process and application fields of siliconits are all related to heavy energy consumption and pollutions, and bring high environmental loads. The resources consumption and pollution emissions in siliconit manufacture process were quantificationally estimated by input/output method. Difference between two traditional techniques to produce siliconits in China was also compared and analyzed. The results show that siliconit manufacture processes consume large quantities of resources because the furnace is open to environment and too much thermal-protection materials are used. For the thick-end technique is more complicated and the thick-end siliconits have a bigger size and mass, there are more resources and energy consumptions and pollution emissions for thick-end process than that for equal-diameter process. Some suggestions were introduced to improve the traditional techniques and a new process was designed. It is the most important that the open furnace should be replaced by close vacuum furnace. Sintering and siliconizing process can be combined into one high-temperature process. As results of process simplification and vacuum sintering, resources and energy consumption and wastes emission can be decreased remarkably.  相似文献   
133.
/ Evaluating the environmental and economic impacts of agricultural policies is not a simple task. A systematic approach to evaluation would include the effect of policy-dependent factors (such as tillage practices, crop rotations, and chemical use) as well as the effect of policy-independent covariates (such as weather, topography, and soil attributes) on response variables (such as amount of soil eroded or chemical leached into the groundwater). For comparison purposes, the effects of these input combinations on the response variable would have to be assessed under competing policy scenarios. Because the number of input combinations is high in most problems, and because policies to be evaluated are often not in use at the time of the study, practitioners have resorted to simulation experiments to generate data. However, generating data from simulation models is often costly and time consuming; thus, the number of input combinations in a study may be limiting even in simulation experiments. In this paper, we discuss the problem of designing computer simulation experiments that require generating data for just a fraction of the possible input combinations. We propose an approach that is based on subsampling the 1992 National Resources Inventory (NRI) points. We illustrate the procedure by assessing soil erosion in a situation where there are "observed" data [reported by the Natural Resources Conservation Service (NRCS)] for comparison. Estimates for soil erosion obtained using the procedure we propose are in good agreement with NRCS reported values.KEY WORDS: Metamodel; National Resources Inventory; Nonpoint source pollution  相似文献   
134.
大力推广中水技术促进循环经济和可持续发展   总被引:2,自引:0,他引:2  
通过对循环经济和可持续化发展,及我国目前正面临着严重的水资源危机的介绍,阐述了采用中水技术,实现污水的资源化,不但可以降低污染,减少污水排放费用,而且是实现循环经济和可持续发展的有效途径,有着很大的社会效益和经济效益。  相似文献   
135.
基于面向对象的北京市区城市内部用地信息提取   总被引:1,自引:0,他引:1  
选取北京市四环以内为研究区域,以资源三号卫星遥感影像为数据源,针对类型多样、特征易混淆的城市内部用地以及高分辨率遥感影像海量信息、人工提取费时费力等特点,论文基于面向对象分类方法,探讨城市内部用地自动提取方法,并对分类结果进行精度评估.结果表明:利用不同地物的光谱、形状、纹理和空间关系等特征,通过多尺度分割和隶属度函数法,构建合理的分类层次,不仅精确提取出研究区内水体、绿地、建设用地和待开发用地,更独具创新地区分了城市建设用地内部各种地物类型,包括工业生产用地、低密度和高密度生活用地以及交通用地.该方法有效地利用了资源3 号卫星影像的光谱、纹理及空间信息特征,总体精度可达到87.00%,Kappa系数达到0.853 9,取得较好的分类效果.  相似文献   
136.
中水回用在沈阳市的应用前景分析   总被引:1,自引:0,他引:1  
沈阳是一个水资源严重短缺的城市,研究中水回用对缓解沈阳用水紧张和节约水资源都有积极的意义。文章研究了沈阳市中水回用的必要性、可行性、现状和制约因素,进而提出了推进沈阳中水回用的有关对策。  相似文献   
137.
本文运用系统动力学原理,构建了徐州市水资源承载力系统SD模型。并利用该模型,研究徐州市水资源承载力在不同发展方案下的变化趋势。最终得出开源、节流、治污并举的综合方案是徐州市水资源可持续发展利用的最优方案,同时指出开源措施对徐州市水资源承载力提高效果最为明显。并有针对性的提出提高徐州水资源承载力的建议与措施。  相似文献   
138.
Resource management as a key factor for sustainable urban planning   总被引:2,自引:0,他引:2  
Due to fast urbanization and increasing living standards, the environmental sustainability of our global society becomes more and more questionable. In this historical review we investigate the role of resources management (RM) and urban planning (UP) and propose ways for integration in sustainable development (SD). RM follows the principle of circular causation, and we reflect on to what extent RM has been an element for urban planning. Since the existence of the first settlements, a close relationship between RM, urbanization and technological development has been present. RM followed the demand for urban resources like water, energy, and food. In history, RM has been fostered by innovation and technology developments and has driven population growth and urbanization. Recent massive resource demand, especially in relation to energy and material flows, has altered natural ecosystems and has resulted in environmental degradation. UP has developed separately in response to different questions. UP followed the demand for improved living conditions, often associated to safety, good manufacturing and trading conditions and appropriate sanitation and waste management. In history UP has been a developing research area, especially since the industrial era and the related strong urbanization at the end of the 18th century. UP responded to new emerging problems in urban areas and became increasingly complex. Nowadays, UP has to address many objectives that are often conflicting, including, the urban sustainability. Our current urban un-sustainability is rooted in massive resource consumption and waste production beyond natural limits, and the absence of flows from waste to resources. Therefore, sustainable urban development requires integration of RM into UP. We propose new ways to this integration.  相似文献   
139.
A national material flow model for concrete, the most popular construction material in Ireland, was developed based on the framework of material flow analysis. Using this model the Irish concrete cycle for the year 2007 was constructed by analysing the material life cycle of concrete which consists of the three phases of: production (including extraction of raw materials and manufacture of cement), usage (ready-mix and other products) and waste management (disposal or recovery). In this year, approximately 35 million metric tonnes of raw materials were consumed to produce 5 million metric tonnes of cement and 33 million metric tonnes of concrete. Concrete production was approximately 8 metric tonnes per capita. By comparison, the concrete waste produced in that year was minimal at only 0.3 million metric tonnes. Irish building stock is young and there was little demolition of structures in the year of study. However this build up of construction stock will have implications for the future waste flows when the majority of stock built in the last decade (43% of residential stock was constructed in the last 15 years) reaches its end of life.  相似文献   
140.
研究构建了我国海洋资源开发利用综合效益评价的指标体系,采用全排列多边形图示指标评价方法,对我国海洋资源开发利用综合效益状况进行了定量评价。结果表明,综合指数在2006年为0.381,在2009年为0.508。评价方法避免了目前评价研究中的弊病,既减少了主观随意性又反映了系统整合原理。  相似文献   
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