Planning for environmental justice in an urban national park

Urban national parks were designed in the 1970s to bring nature and recreational opportunities to socio-economically disadvantaged communities in the USA. Using the theoretical frame of environmental justice, this paper discusses findings of a recent survey of visitors to Los Angeles' Santa Monica Mountains National Recreation Area – the United States' largest urban national park. Findings show park visitors were predominantly white, affluent, and lived nearby. People of colour travelled further, were significantly less likely to be return visitors, and were less inclined to use the park for active recreation. Seemingly, this park fails to meet the needs of the disadvantaged urban communities for whom it was created, a problem that may also affect other parks in the United States and potentially parks in other countries. Park planners and managers can take practical steps to increase accessibility to this park for people of colour and low-income earners, and should monitor other parks for patterns of ethno-racially differentiated access and utilisation.     

基于不同出行方式的城市微观主体碳排放研究

从城市微观主体的角度出发,通过构建城市微观主体碳排放评测模型,探讨了城市微观主体土地利用模式对碳排放的影响。以南京市某单位为例,采用交通周转量与连续逼近法,对研究单位园区间流通带来的碳排放进行了评测。结果表明,交通方式的选择对碳排放量的影响较显著,不同交通方式的碳排放量排序为:城市公交<综合交通<单位通勤<私人轿车。     

基于分形理论的皖江城市带城镇体系结构研究

运用分形理论对皖江城市带城镇体系的规模分布和城镇空间结构进行了具体分析,得出如下结论:在城镇规模分布方面,城市规模结构分布较为集中,中等位序的城市较多,首位城市作用不显著,人口分布低水平均衡;在城镇空间结构方面,城镇之间的空间关联程度、空间相互作用一般,空间布局较分散。在此基础上,提出了未来皖江城市带城镇体系发展的相应对策。     

地方文化在城市雕塑设计中的表达——以山东省威海市海滨雕塑为例

城市雕塑是城市文化的载体,具有重要的文化意义,但目前我国城市雕塑缺乏地方文化特色的现象较突出.在对国内外相关研究文献回顾的基础上借鉴雕塑设计、景观设计、旅游规划和公共艺术设计的研究成果,确定了城市地方文化在城市雕塑设计中表达的理论与方法以及相应的实施程序,并以山东省威海市为例进行了理论验证,提出了新型城市雕塑的概念设计与实施建议.     

国外屋顶绿化推广的政策分析与启示

分析了屋顶绿化的生态价值和经济效益,介绍了国内外屋顶绿化政策及实施情况,探讨了如何在我国城市化进程中,通过相关政策和技术标准的运用,不断推广屋顶绿化,充分发挥其对城市环境保护和生态服务的作用。     

Assessment Tools for Urban Catchments: Developing Stressor Gradients1

Abstract: This is the first in a series of three articles designed to establish empirically defined biological indicators and thresholds for impairment for urbanized catchments, and to describe a process by which the biological condition of waterbodies in urbanized catchments can be applied. This article describes alternative gradients of urbanization for assessing and selecting a nationally applicable biological index (article 2 – Purcell et al., this issue ) and defining the potential of biological communities within a gradient of cumulative stressors (article 3 – Paul et al. this issue ). Gradients were designed to represent the most prominent mosaic of stressors found in urban settings. A primary urban gradient was assembled based on readily obtained information of urbanization to include three broad‐scale parameters: percent urban land use/land cover, population density, and road density. This gradient was used as the standard by which alternative urban gradients, which included fine‐scale instream chemical and hydrologic parameters, were assessed. Five alternative gradients were developed to provide numerous environmental management options based on availability of data from water program resources. The urban gradients were developed with the intent that they be applied throughout the country; therefore, data from three different regions of the United States (Mid‐Atlantic, Midwest, and Pacific Coast) were used to validate the urban gradient model. Our study showed that a relatively straightforward stressor gradient consisting of human population density, road density, and urban land use is useful in providing a framework for developing relevant biological indicators and evaluating the potential of biological communities as a basis for assessing attainment of designated aquatic life use.     

Bags with oven-dried moss for the active monitoring of airborne trace elements in urban areas

To define a harmonized methodology for the use of moss and lichen bags as active monitoring devices of airborne trace elements in urban areas, we evaluated the element accumulation in bags exposed in Naples in different spring weather conditions for 6- and 12-weeks. Three different pre-exposure treatments were applied to moss and lichen materials: water-washing, acid-washing and oven-drying. During the different exposure periods in the Naples urban environment the moss accumulated always higher amounts of elements (except Hg) than lichens and the element accumulation increased during wetter weather and higher PM₁₀ conditions. The oven pre-treatment did not substantially modify the morphology and element composition of moss and the exposure in bags of this material for 6-weeks was sufficient to detect the pattern of airborne trace elements.     

基于Agent的城市污水处理可持续发展工艺选型定量建模研究

从可持续发展的角度分析和研究中国目前的城市污水处理工艺,选出符合中国国情的工艺流程日益成为迫切需要解决的问题.在广泛调研和资料分析的基础上,基于可持续发展的原则,通过对中国城市污水处理的现状进行分析,建立了可供筛选的处理技术数据库,并通过基于生命周期的Agent模型,对每项组合工艺流程进行功能模拟和性能评价,按照所建立的评价模型和指标体系,综合考察各项处理工艺的污染物处理水平、投资成本和附属产物的环境影响等因素.按照可持续发展的技术准则进行判定,从而选择满足可持续发展要求的城市污水处理组合工艺.     

南通市城镇建设用地扩展时空特征分析及模拟

随着工业化与城市化步伐的加快,城镇建设用地高速扩张,建设与粮食生产的矛盾日益突出,如何合理有效使用土地成为城市快速发展过程中迫切需要解决的问题。通过多时相遥感卫星影像,结合相关模型,分析和模拟建设用地扩展的时空特征,可以为城市土地合理配置与投放提供依据。利用 1987、1990、1997、2001、2006年的TM卫星遥感影像解译获得的建设用地数据,分析了南通近 20年来城镇建设用地变化和城区扩展特征,并且模拟了其扩展趋势。结果表明：南通市城镇建设用地扩展呈现明显的阶段性特征;其扩展的热点主要集中在沿江区域,沿海地区城镇建设用地扩展的热度逐步升温;城镇建设用地扩展显示出城镇组团化发展的趋势,尤其使南通大都市区的轮廓日益明晰。     

武汉市主要绿化树种滞尘效应研究

本实验对武汉市城区主干道主要绿化树种的滞尘效应与叶表面结构进行了研究。结果表明：（1）同一尘源条件下,不同树种的滞尘能力差异显著。乔木中悬铃木滞尘能力较高,可达6.9345 g/m²;小乔木中紫薇和紫叶李是滞尘能力较高的树种,滞尘能力分别为1.9543 g/m²和1.8790 g/m²;灌木中红花檵木和杜鹃等有较强的滞尘能力,分别可达4.0373 g/m²和3.8875 g/m²;（2）利用扫描电镜观察叶表面结构发现：叶表具毛被、褶皱、较深的不规则网格等特征的树种滞尘能力较高,叶表平滑或叶表网格结构规则且较浅时滞尘能力较低;（3）同一树种在不同的尘源条件下滞尘能力差异显著,空气中颗粒物浓度越高,滞尘能力也越大。以车流量近似模拟尘源条件表明,滞尘能力与车流量呈正相关。