论城市创新的生态思维--推动城市可持续发展的新思维

城市化是人类生产和生活方式转型的必然结果,由于城市建设过程中依照的是传统思维模式,导致各大城市均不同程度存在一定的城市病。因此要加强可持续发展生态思维的观念,以期推动我国城市生态化与可持续城市建设工作的开展。     

公众参与市容环境规划与管理的方法设计--以南京市的实践为例

市容环境是与公众生活联系最为紧密的领域,也是公众参与最容易进行的领域。南京的城市建设要实现“经济发达、环境优美、融古都特色和现代文明于一体的现代化江滨城市”的目标,公众参与市容环境的规划与管理是关键内容之一。论文以“南京市市容环境卫生发展规划”项目工作为基础,分析和阐述公众参与的内涵,提出公众参与市容环境的五大步骤,并针对南京市容环境方面的具体案例,设计出符合南京特色的公众参与市容环境规划与管理的方法框架模型,包括决策模式、制度框架的共管体系。     

Numerical Prediction of Dispersion Characteristics in an Urban Area Based on Grid Refinement and Various Turbulence Models

A detailed simulation of the Goettinger Strasse pollutantdispersion problem is performed using the CFD code CFX-TASCflow for different wind directions. Two turbulencemodels, the k- and the RSM are adopted on three gridrefinement levels. Besides the typical reference gridimplemented by the TRAPOS group, two different gridresolutions are introduced. The first refinement is in thewhole street canyon region on the x-y level, while thesecond one is local in all three directions. Validation ofall involved computational schemes is performed based onrelative available experimental data. The computed velocityfields and concentration contours imply that the typicalreference grid is a suitable choice for the velocityfields, while local grid refinement in all three directionsin a small region containing the receptor is required toupgrade the pollutant concentration results with modestadditional computational effort. Finally the RSM modelresulted in smaller concentration levels. The k-model compared to the RSM seems a more appropriate choiceto solve this particular problem.     

Atmospheric Levels of Nitrogen Oxides at a Greek Oil Refinery Compared with the Urban Measurements in Athens

Oil refining is among the industrial activities that emit considerable amounts of air pollutants into the atmosphere. Nitrogen oxides are important air pollutants that are emitted by oil refineries as products of combustion processes. The ambient air concentrations of nitrogen oxide (NO) and nitrogen dioxide (NO₂) were monitored continuously at a site close to an oil refinery, near the city of Corinth in Greece, during autumn 1997 together with the main meteorological parameters. The contribution of the oil refinery to the measured atmospheric levels of nitrogen oxides was estimated. The ambient air concentration of nitrogen oxides in the area surrounding the oil refinery were generally lower than the ambient air concentrations in the urban area of Athens in Greece, and the NO₂ levels were always below the existing air quality standards. The influence of the refinery emitted NO_x in the photochemical production of ozone seems to be more important in terms of human and vegetation exposure given the high ozone backgrounds measured in the area.     

River systems as providers of goods and services: a basis for comparing desired and undesired effects of large dam projects

In developing countries, large dam projects continue to be launched, primarily to secure a time-stable freshwater supply and to generate hydropower. Meanwhile, calls for environmentally sustainable development put pressure on the dam-building industry to integrate ecological concerns in project planning and decision-making. Such integration requires environmental impact statements (EISs) that can communicate the societal implications of the ecological effects in terms that are understandable and useful to planners and decision-makers. The purpose of this study is to develop a basic framework for assessing the societal implications of the river ecological effects expected of a proposed large dam project. The aim is to facilitate a comparison of desired and potential undesired effects on-site and downstream. The study involves two main tasks: to identify key river goods and services that a river system may provide, and to analyze how the implementation of a large dam project may alter the on-site capacity and downstream potentials to derive river goods and services from the river system. Three river goods and six river services are identified. River goods are defined as extractable partly man-made products and river services as naturally sustained processes. By four main types of flow manipulations, a large dam project improves the on-site capacity to derive desired river goods, but simultaneously threatens the provision of desirable river goods and services downstream. However, by adjusting the site, design, and operational schedule of the proposed dam project, undesirable effects on river goods and services can be minimized.     

Traditional Land-Use Systems and Patterns of Forest Fragmentation in the Highlands of Chiapas, Mexico

The influence of slash-and-burn agriculture and tree extraction on the spatial and temporal pattern of forest fragmentation in two municipalities in the highlands of Chiapas, Mexico was analyzed. The data series were derived from two subsets of satellite images taken in 1974 and 1996. The analysis was based on area, edge, shape, core area, and neighbor indices. During the 22 years, the dense forest decreased by 8.9%/yr in Huistán and by 8.6%/yr in Chanal, while open/disturbed forest, secondary vegetation, and developed area increased in both municipalities. The total number of fragments increased by 1.4%/yr and 2.3%/yr in Huistán and Chanal, respectively. Dense forest showed the highest increase in the number of fragments (6%/yr in Huistán and 12%/yr in Chanal), while edge length, core area, and number of dense forest core areas decreased. The larger fragments of dense forest present in 1974 were divided into smaller fragments in 1996; at the same time, they experienced a process of degradation toward open/disturbed forest and secondary vegetation. Two different fragmentation patterns could be distinguished based on agricultural or forestry activities. Forest fragmentation did not occur as a continuous process; the pattern and degree of fragmentation were functions of land tenure, environmental conditions, and productive activities. The prevalence of rather poor soil conditions, small-holdings, growing human population densities, increasing poverty, and the absence of alternative economic options will maintain a high rate of deforestation and forest fragmentation in the studied region.     

城市灾害学研究及科学建议

无论从哪个角度来看,２０世纪都是历史发展最快,发生事件最多的一个世纪。城市由于是对时代脉搏最敏感空间地域,所以,时时处处反映出时代的特点。城市灾害作为现代及未来灾害的集中反映,越来越成为严峻的话题。无论承认与否,城市化发展进程中将始终伴随着灾情。笔者认为,惟有直面灾情,全面关注城市灾害及其在中国减灾中的地位与作用,才有希望走向未来,并创造城市安全“时空”。     

恢复生态学研究的一些基本问题探讨

对恢复生态学的研究概况、基本概念、内涵与研究内容以及生态恢复的目标、原则、程序与技术进行了分析与探讨，指出恢复生态学应加强基础理论研究和应用技术研究。生态恢复与重建是指根据生态学原理，通过一定的生物、生态和工程技术，人为地切断生态系统退化的主导因子和过程，调整和优化系统内部及其与外界的物质、能量和信息的流动过程及其时空秩序，使生态系统的结构、功能和生态学潜力尽快成功地恢复到原有的乃至更高水平。     

欠发达城市人居环境评价体系构建及应用

在参阅国内城市人居环境评价指标体系研究的基础上，选择安徽省六安市为样区，提出了欠发达城市人居环境评价的原则、指标构成以及评价模式和方法。其中，指标体系共分为目标层、准则层、分类层和指标层4个层次，从居住建设、生态环境和社会经济三大系统构建了39个单项指标，依据六安市2005年的调查统计资料，对其人居环境的建设水平和满意度两方面进行了对比评价，验证结果科学可行，可为同类地区人居环境质量评价提供参考。