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241.
Research increasingly highlights cause and effect relationships between urbanization and stream conditions are complex and highly variable across physical and biological regions. Research also demonstrates stormwater runoff is a key causal agent in altering stream conditions in urban settings. More specifically, thermal pollution and high salt levels are two consequences of urbanization and subsequent runoff. This study describes a demonstration model populated with data from a high gradient headwaters stream. The model was designed to explain surface water‐groundwater dynamics related to salinity and thermal pollution. Modeled scenarios show long‐term additive impacts from salt application and suggest reducing flow rates, as stormwater management practices are typically designed to do, have the potential to greatly reduce salt concentrations and simultaneously reduce thermal pollution. This demonstration model offers planners and managers reason to be confident that stormwater management efforts can have positive impacts.  相似文献   
242.
城市轨道交通噪声的声源特性研究进展   总被引:1,自引:0,他引:1  
分析了城市轨道交通噪声的主要类型、基本特性、传播规律及其影响因素;综述了国内外城市轨道交通噪声的预测及测量分析技术的研究成果,并对其进行了总结比较,阐述了各种方法的特点、主要成就和局限;最后探讨了城市轨道交通噪声领域今后的研究方向和发展趋势,为解决城市轨道交通发展中的噪声问题提供了参考.  相似文献   
243.
基于超临界水氧化过程的能源环境系统设计   总被引:2,自引:0,他引:2  
阐述了超临界水氧化过程的工艺路线,介绍了超临界水氧化过程的特点,提出了基于超临界水氧化过程的能源环境系统,设计了几种热量与能量回收系统程的耦合工艺,为提高超临界水氧化过程的经济性奠定了基础。  相似文献   
244.
This paper describes a GIS-based estimation method that can be used to forecast future amounts of impervious surface as a mitigation measure for urban heat island effect in a metropolitan region. The method is unique because it employs a regression model that links the existing amount of impervious surface to population and employment at the census tract level. This approach provides a means to forecast future amounts of impervious surface based on projected population and employment. The method also includes a detailed analysis of high-resolution aerial photography to divide impervious surfaces into different categories. Subdividing impervious surfaces is necessary to evaluate potential urban heat island mitigation policies for different types of impervious surface. The analysis here shows that the impervious surface in the metropolitan Atlanta region will increase to 2638 km2 2. “The Albedo is defined as the hemispherical reflectivity averaged over the solar spectrum. A perfect reflector has a = 1, and a perfect absorber has a = 0” (Pomerantz et al. 1999 Pomerantz, M. 1999. Reflective surfaces for cooler buildings and cities. Philosophical magazine B, 79: 14571476. [Taylor & Francis Online], [Web of Science ®] [Google Scholar], p. 1458). View all notes in 2030, an increase of 45% from 2000. The most common type of impervious surface is dark-coloured pavement. Within this study area, the analyses showed that two-thirds of impervious surfaces are dark. Replacing dark pavement with light pavement materials, therefore, represents an important opportunity to mitigate the urban heat island effect in the Atlanta region.  相似文献   
245.
探讨了建国后山东城乡人口布局的历史演变特征,分析了自然因子和人文因子对城乡人口空间布局的影响,对城乡人口年龄结构、经济结构和文化素质结构进行了比较分析。通过分析得出,建国以后山东城乡人口布局在城市化进程中不断优化,特别是改革开放以后,城乡人口布局演变加快,说明经济快速发展成为推动城乡人口布局变动的主要因素。  相似文献   
246.
Household consumption is one of the important factors that induce COL emission. Based on input-output model, this article calculated the intensity of CO2 emission of different income groups and seven provinces in China, and then estimated total CO2 emission induced by urban household consumption from 1995 to 2004 in China based on statistic data of household living expenditure. The results show that CO2 emission per capita induced by household consumption had increased from 1583 to 2498 kg CO2 during 1995-2004. The ratio of consumption-induced CO2 emission to total CO2 emission had risen from 19% to 30% in the past decade. Indirect CO2 emission accounted for an important part of the consumption-induced emission, the ratio of indirect emission to consumption-induced emission had risen from 69% to 79% during the same period. A significant difference in consumption-induced CO2 emission across different income groups and different regions has been observed. COs emission per capita of higher income groups and developed regions increased faster than that of lower income groups and developing regions. Changing lifestyle has driven significant increase in CO2 emission. Especially, increases in private transport expenditure (for example, vehicle expenditure) and house building expenditure are key driving factors of growth in consumption-induced COL emission. There are big differences in the amount of CO2 emission induced by change in lifestyle across different income groups and provinces. It can be expected that lower income households and developing regions will increase consumption to improve their livings with income growth in the future, which may induce much more CO2 emission. A reasonable level of CO2 emission is necessary to satisfy human needs and to improve living standard, but a noticeable fact is that CO2 emission per capita induced by household consumption in developed areas of China had reached a quite high level. Adjustment in lifestyle towards a low-carbon society is in urgent need.  相似文献   
247.
上海都市旅游与长三角区域旅游的互动响应   总被引:4,自引:0,他引:4  
随着经济全球化和区域一体化进程的加速,从长江三角洲地区区域旅游发展的视角重新审视上海都市旅游发展,探析都市旅游与其周边区域旅游发展的互动响应,具有重要的先导和示范效应。基于上海都市旅游发展面临挑战及长三角区域旅游合作进程的梳理,在对长三角旅游城市体系规模结构、长三角城市旅游经济联系度等指标的测评分析与研究基础上,提出上海都市旅游与长三角区域旅游互动响应路径首先是长三角核心城市(上海 南京 杭州)网络化发展,通过旅游产业网络化、市场网络化、组织网络化、服务保障体系网络化等各个子(分)网络共同构成互补、协作和理性竞争的长三角大旅游产业体系,尝试构筑“上海都市旅游 长三角区域旅游”共轭型的旅游地域综合体,旨在推进上海都市旅游与长三角区域旅游的和谐可持续发展,进而提升长三角区域旅游的整体竞争优势。  相似文献   
248.
Landscape-geochemical features providing for manifestation of gigantism in herbaceous plants have been revealed in natural habitats in the south of Sakhalin and Kunashir islands. Tall herb assemblages have proved to be associated with geochemical landscapes characterized by reducing (gley or hydrogen sulfide) conditions and increased contents of petroleum hydrocarbons and some trace elements (total and movable forms). A hypothesis is put forward that gigantism in herbaceous plants is manifested in zones of active faults, which serve as a kind of conduits supplying endogenous heat, matter, and water to the root systems.  相似文献   
249.
Both the Aalborg Commitments and the guidance on integrated urban environmental management and sustainable urban transport plans proposed by the EU Thematic Strategy on the Urban Environment foresee a baseline review as the first step in developing integrated urban management plans and systems. A baseline review of urban sustainability undertaken in Riga reveals significant discrepencies between the sustainability criteria of the Aalborg Commitments and the: responsibilities and competencies of the municipal government and administration as defined by statutes; policy goals and measures defined in municipal planning documents; policy goals and measures defined in the Riga Development Plan. To better orient the mandate of the municipality towards sustainable development, municipal statutes should be supplemented to more fully reflect the issues defined by the Aalborg Commitments and should include sustainability as a goal. In order to strengthen the implementation of sustainable development specific policy goals, measures and targets should be formulated for all the Aalborg Commitments issues when revising existing municipal planning documents or developing a municipal sustainable development management plan. An analysis of the European Common Indicators and the State of the Environment in Riga 2001 indicators indicates that they can only partially fulfill a monitoring function for the implementation of the Aalborg Commitments. This highlights a need to better coordinate sustainable development initiatives at the European level. The methodology used for the baseline review in Riga is useful for assessing the status of urban sustainability when preparing integrated urban management plans or systems, but requires testing elsewhere. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
250.
介绍了高炉煤气的主要燃烧特性,分析了高炉煤气在循环流化床锅炉中掺烧时对炉膛换热、过热蒸汽温度、锅炉负荷、热效率、分离装置以及环境的影响,并提出了消除不良影响的相应措施。  相似文献   
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