The common language of space: a way of looking at the social,economic and environmental functioning of cities on a common basis

１　ＳｏｍｅｑｕｅｓｔｉｏｎｓａｎｄａｎｓｗｅｒｓａｂｏｕｔｃｏｍｐｌｅｘｉｔｙＴｈｅｆｉｒｓｔｓｅｎｔｅｎｃｅｉｎａｎｙｄｉｓｃｕｓｓｉｏｎａｂｏｕｔｔｈｅｓｃｉｅｎｃｅｏｆｃｉｔｉｅｓｕｓｕａｌｌｙｃｏｎｔａｉｎｓｔｈｅｗｏｒｄ“ｃｏｍｐｌｅｘｉｔｙ”．Ｏｎｅｏｆｔｈｅｍｏｓｔｏｂｖｉｏｕｓｆｏｒｍｓｔｈｉｓｔａｋｅｓｉｓｔｈｅｓｈｅｅｒｐｈｙｓｉｃａｌａｎｄｓｐａｔｉａｌｃｏｍｐｌｅｘｉｔｙｏｆｔｈｅｃｉｔｙａｓａｎｏｂｊｅｃｔ．Ｔｈｅｒｅｉｓ,ｈｏｗｅｖｅｒ,ｉｎｍｏｓｔｕｒｂａｎｒｅｓ…     

Assessing London,Ontario's brownfield redevelopment effort to promote urban intensification

Intensification of existing urban areas is currently a major item on the policy agenda of the Ontario and Canadian governments. As part of the urban intensification drive, brownfield sites have become major candidates for redevelopment. Governments at all levels have initiated policies and programmes to encourage their remediation and redevelopment. This paper reports the findings of a qualitative exploration of brownfield redevelopment in London, Canada. Through in-depth interviews (n?=?17) with key stakeholders involved in brownfield redevelopment, the study explores the level of participation in brownfield redevelopment, barriers to brownfield redevelopment in the city, and perceptions about financial incentives in the city's Brownfield Community Improvement Plan. The study found that despite the availability of financial incentives, the overall private sector participation in brownfield redevelopment is low due to barriers such as competition from greenfield, risk, cost, negative public perception of brownfields, and complex remediation processes. The paper provides policy suggestions that may contribute to a more active participation in brownfield redevelopment in the city.     

Integrated environmental assessment: an urban perspective

１　ＩｎｔｒｏｄｕｃｔｉｏｎＵｒｂａｎａｒｅａｓｔｈｒｏｕｇｈｏｕｔｔｈｅｗｏｒｌｄａｒｅｉｎｃｒｅａｓｉｎｇｌｙａｆｏｃｕｓｏｆｅｎｖｉｒｏｎｍｅｎｔａｌｃｏｎｃｅｒｎ．Ｔｈｅｙａｒｅｐｌａｃｅｓｏｆｉｎｔｅｎｓｅａｎｄｇｒｏｗｉｎｇｅｃｏｎｏｍｉｃａｃｔｉｖｉｔｙ．Ｉｎｒｅｓｐｏｎｓｅ，ｕｒｂａｎｐｏｐｕｌａｔｉｏｎｓａｒｅｇｒｏｗｉｎｇｒａｐｉｄｌｙ．Ｉｔｉｓｅｓｔｉｍａｔｅｄｔｈａｔ，ｂｙ２０００，ｍｏｒｅｔｈａｎｈａｌｆｔｈｅｗｏｒｌｄ○ｓｐｏｐｕｌａｔｉｏｎｗｉｌｌｌｉｖｅｉｎｔｏｗ…     

上海与伦敦城市绿地的生态功能及管理对策比较研究

在资料收集及实地采样调查的基础上 ,文章对上海与伦敦城市绿地的生态功能及管理对策进行了比较分析 ,指出了上海城市绿地建设及管理中的一些优点及不足之处。     

有机粘土疏水性吸附过程的分子模拟:烷基碳原子数和有机物logK_(ow)的影响

基于从分子尺度上解析改性剂烷基碳原子数和有机物疏水性对有机粘土吸附能力的影响机制,以从头算的量子化学计算方法(MP2/6-31g(d))模拟了有机粘土在水溶液中的吸附过程.通过计算吸附前后几何构型、能量、化学键和电荷分布等参数的变化,分析了影响有机粘土疏水性吸附的关键因素,并对疏水性吸附作用力的化学本质进行了初步探讨.计算结果表明,烷基碳原子数增加对提高有机物吸附能的作用并不显著,长链烷基提高有机粘土吸附容量的真正原因在于其可提供更多的有机物吸附位.有机物的疏水性(以正辛醇-水分配系数logKow表征)是影响疏水性吸附过程的关键因子,水分子的引力作用对疏水性吸附具有决定性影响,理论上解释了普遍存在的有机物吸附量与logKow呈正相关的实验现象.疏水性吸附力的作用前提是有机物为疏水性,即当水分子的引力作用较弱时疏水性作用力才可以表现出来;而对于亲水性有机物,疏水性吸附力会被水分子的引力所抵消,吸附强度减弱.模拟红外光谱和电荷分布结果表明,吸附前后无化学键断裂和电子得失的发生,只有原子电荷密度的微小变化,据此推测疏水性吸附力以分子间弱相互作用力——London色散力为主.     

Further studies on the influence of zeolite type A on metal transfer in the activated sludge process

Investigations were carried out to determine the effect of zeolite type A on metal removal by activated sludge using laboratory activated sludge simulations. They were operated at constant aerator sludge age and settler surface loading. Different concentrations of raw zeolite and zeolite extracted from washing powder (0, 15, 30, 60, 120 mgl^?1) were introduced into the simulations. The zeolite was added at two degrees of calcium exchanged for sodium, 25 and 75% of the maximum exchange capacity. Metals were added at concentrations typical of mixed domestic-industrial waste waters. The results show that there was no adverse effect on metal removal by the laboratory activated sludge simulations in the presence of zeolite type A.     

The Application of A Tiered Testing Approach to the Management of Dredged Sediments for Disposal at Sea in Canada

Canada, and other signatories to the London Convention 1972 on the prevention of marine pollution by dumping, are preparing to ratify a 1996 Protocol to this convention. Among the improvements to this international agreement, is a new process for the Assessment of Waste and Other Matter, which is to be adopted by signatory parties. the process includes a step in which material considered potentially acceptable for sea disposal must be characterized by chemical, physical and biological properties. Canada's interpretation and intended implementation of this characterization step is presented for the assessment of dredged sediments. This tiered testing approach involves using chemical screening limits for contaminants, and biological testing when screening levels are exceeded. Dredged material containing specified substances (e.g., cadmium, mercury, PAHs, PCBs, etc.) below or at screening levels would generally be considered of little environmental concern for disposal at sea. Wastes above the screening levels would require more detailed assessment before their suitability for disposal at sea could be determined.     

RESEARCH INTO THE EFFECTS OF ARTIFICIAL GROUNDWATER RECHARGE,LEA VALLEY,LONDON ENGLAND1

ABSTRACT: Large-scale groundwater abstraction from the Cretaceous Chalk/Lower Tertiary Basal Sands aquifer system of the London Basin in the last 150 years has developed storage of more than 1000 Mm³. Limited operational recharge was undertaken in the 1950's encouraging further detailed study of the wider possibilities. Following a comprehensive hydrogeological reappraisal, an economic and engineering study and pilot-scale experiments, the Lea Valley has been shown to have the greatest potential for recharge. Artificial recharge into the Chalk at a rate of 9000 m³/d appears possible, through acidised 900 mm diameter boreholes. An understanding of the degree of interconnection between the Chalk and Basal Sands and of the causes of changes in quality of recharged water during storage was shown to be of particular importance to the successful operation of any recharge scheme using this system. A two-layer numerical groundwater model of the 800 km² area and a surface/groundwater simulation model have been used to assist with the design of the 84,000 m³/d prototype scheme, and will also help in assessing its efficiency. The models will ultimately be used to manage the operation of the first stage development, now coming into use.     

Assessment of Air Quality, Emissions and Management in a Local Urban Environment

This paper describes one example of how the UK National Air Quality Strategy (NAQS) is implemented in a local urban environment. The paper reviews the beginning of this process, by examining the review and assessment procedures of the NAQS in the London Borough of Barnet. By the application of available UK tools of local air quality management (LAQM), the process began through analysis of the levels of local emissions and progressed onto modelling of current and future air quality. A map showing combined emission hotspot areas for the Borough indicated and higher emission rates occur in the south of the Borough and along the major transport corridors, as road sources dominate emissions. Dispersion modelling studies were also conducted for this purpose, using the screening models GRAM, PGRAM and ADMS Urban for an in-depth assessment. These analyses found that some local point sources and the majority of Borough roads with over 20,000 vehicles per day produced exceedances of the future objectives for air quality for some pollutants.Recommendations for the progression of LAQM in the Borough are made and include the update and expansion of the emissions information held for use in future modelling studies. The paper demonstrates the experience of implementing the Strategy, using the tools and procedures available for this purpose, in a local urban environment that is similar to many in the UK.