城市交通噪声对高层建筑的影响及声屏障优化设计研究

结合案例分析交通噪声对临路高层建筑声环境的影响,随着楼层的变化,噪声贡献值呈现抛物线型变化。在第3层～第5层处噪声值达到最大,然后随着楼层增加噪声值逐渐减小;此外低楼层处夜间噪声超标严重。在隔声设计时应重视噪声最大值出现的位置及夜间时段的噪声影响,增加声屏障的高度对提高低楼层隔声效果有较明显作用。对于临路高层建筑,单一的声屏障措施的降噪效果有限且有众多限制因素,采取声屏障＋隔声窗措施有较好的降噪效果。     

下凹式绿地在降雨径流控制中的应用研究

下凹式绿地具有蓄渗雨水、削减洪峰流量、净化雨水、防止土壤侵蚀等优点,且投资少,是一种能同时满足环境、生态、经济等多重效应的新型雨水利用措施;它的应用将有效缓解城市水资源匮乏和降雨地表径流造成的面源污染,同时能在一定程度上防止城市内涝.在介绍下凹式绿地对降雨径流控制的基础上,着重综述了下凹式绿地对雨水的蓄渗、净化作用及其设计方面的研究进展.     

Sustainable graywater reuse for residential landscape irrigation – a critical review

The demand for potable water is rising rapidly due to an ever-increasing population, economic activities, and dwindling water supplies. To provide adequate water supplies in the future, understanding the issues and challenges in the reuse of water and developing appropriate strategies for reuse will be critical. One way to augment water supplies for residential use is to reuse graywater – the wastewater from kitchens, bathrooms, and laundries. In this article, we critically review the evolution of water reuse, the definition of graywater, graywater reuse practices, volumes and flow in different situations, and graywater characteristics. We then examine the issues associated with different graywater treatment methods and how using graywater for irrigation around homes affects soil quality and plant growth. The study concludes that graywater treatment costs, human health risks, and its effect on soil quality are some of the challenges that need to be addressed in the future for widespread and sustainable reuse of graywater for irrigation around homes.     

长江经济带开发构想与发展态势

长江经济带是我国国土开发和经济建设中极其重要的开发轴线,近年来已经上升为新一轮的国家战略,肩负着参与国际竞争、协调东中西3大区域、推进双向开放、建设生态文明的使命。在国际国内经济社会发展新形势下,长江经济带发展机遇与挑战并存。以流域经济发展为视角,从长江经济带提出的背景出发,回顾了长江经济带战略构想及20世纪80年代以来开发历程,从经济地位、产业集聚、航运建设、岸线开发、沿江交通等5个方面分析了长江经济带发展态势,并重点分析了长江经济带重化工业发展与布局、生态环境影响、港口建设与发展、城市群培育等方面面临的主要问题,最后从改革考核机制、破除行政壁垒、强化流域协调机构与建立流域管理法律法规等方面提出了对策思路,以期为新时期长江经济带开发建设提供参考借鉴。     

“城郊乡”梯度下土壤Cu、Zn、Pb含量的空间变异特征

为揭示城市化、工业化等人为活动对土壤环境质量的影响,选择能反映上海城郊乡梯度差异的中心城区、城郊结合部和远郊,采用地统计学方法对表层土壤样品Cu、Zn、Pb的空间变异结构和分布特征进行了对比分析。结果表明:城市土壤Pb、Cu、Zn的变异系数范围为0.24~0.62,均属中等变异强度。徐汇区土壤Cu、Pb、Zn符合正态分布,闵行区土壤Cu、Pb和Zn符合对数正态分布,奉贤区土壤Zn呈正态分布,土壤Cu、Pb符合对数正态分布。由中心城区到远郊,城市土壤Cu、Pb、Zn的各项统计特征值和变异系数均有较大差异,存在明显的空间分布差异。半方差函数分析结果表明,徐汇区作为中心城区,土壤Cu、Pb、Zn符合球状模型,土壤Cu、Zn具有强烈的空间相关性,土壤Pb具有明显的空间自相关。奉贤区以农业用地为主,土壤Pb符合线性模型,土壤Cu符合高斯模型,土壤Zn符合指数模型,具有强烈的空间相关性。闵行区地处城郊结合部,土壤Cu、Pb、Zn的半方差拟合模型均为线性模型,表现为纯块金形式,以随机变异为主,空间相关性弱。采用Kriging最优内插法进行无偏估值,绘制了表层土壤重金属含量的空间分布图,中心城区、城郊结合部、郊区土壤重金属的空间分布受城市化、工业化、城市交通等因素的影响,均表现出不同的空间分布规律。     

基于圈层建设用地密度分析的中国主要城市扩张的时空特征

基于圈层建设用地密度分析,提出了城市扩张核心度指数;通过计算城市扩张核心度指数和城市扩张强度指数,分析了1990~2010年中国27个主要城市距城市中心不同距离区域的城市扩张的时空模式。研究发现:(1)1990~2010年,大部分城市核心度指数不断降低,城市空间结构变化与国家区域政策密不可分,呈现明显的区域特征。1990~2000年东部沿海地区城市核心度值减少幅度较大,2000~2010年则是东北部和中西部城市降低明显。总体上看,西部和东北部城市的核心度指数要高于东部和中部的城市,结构更加紧凑。(2)城市扩张最活跃的地方总是出现在核心区边界附近,并不断向外推移。(3)城市的形态与城市的发展阶段密切相关。1990~2000年,一线城市扩张的强度和范围远大于其他城市;2000~2010年,二三线城市的扩张强度和范围明显增加。经济比较发达的城市,建设用地的扩张逐渐由单中心扩展向多中心协同发展转变,而经济相对落后西部城市和东北部城市,城市结构比较紧凑,保持着单中心的城市形态。     

典型河谷城市儿童土壤与灰尘铅暴露风险

为定量评价河谷型城市土壤与灰尘铅对城市儿童健康的影响与风险,结合野外调查的基础上,以陕西渭河谷地典型工业城市宝鸡、西安、渭南和铜川为研究区域,以定量分析河谷型城市儿童环境铅暴露为核心,收集4个城市土壤与灰尘分析样品总计243个。利用X射线荧光光谱法测定了4个城市土壤与灰尘铅的含量;采用BCR连续形态分级法探究了城市土壤与灰尘重金属铅地球化学形态分布与迁移特征;根据US EPA污染物暴露与健康风险评价模型对城市儿童铅暴露进行了评价。研究结果表明渭河谷地典型城市宝鸡、铜川、西安和渭南城市土壤与灰尘铅浓度(X±SD)分别为(409.2±52.54)和(624.70±66.15)mg·kg-1、(357.47±41.37)和(592.60±36.78)mg·kg-1、(61.4±13.31)和(78.42±14.89)mg·kg-1、(46.71±12.11)和(64.7±13.76)mg·kg-1,均高出陕西省土壤铅背景值;污染水平依次为宝鸡铜川西安渭南。4个河谷型城市土壤与灰尘重金属铅发生整体迁移的趋势为:宝鸡城市灰尘(90.71%)西安城市灰尘(84.74%)≥宝鸡城市土壤(83.12%)渭南城市灰尘(74.89%)≥西安城市土壤(74.50%)铜川城市灰尘(72.49%)铜川城市土壤(57.50%)渭南城市土壤(53.79%)。可见,铅在均在城市灰尘中的迁移趋势远大于相应的城市土壤。4个城市土壤与灰尘均表现出较大的儿童暴露致癌风险,宝鸡和铜川城市儿童土壤与灰尘铅暴露也分别存在非致癌风险,风险程度依次为宝鸡铜川西安渭南。儿童铅暴露致癌与非致癌风险程度与其城市土壤和灰尘中铅可氧化态分布呈相似的规律,表明碱性的城市土壤与城市灰尘(p H7)中可氧化态铅可能是导致河谷型城市儿童铅暴露风险和儿童血铅污染的主要形态和因素。由此,城市燃煤排放与含铅制品的加工等活动可能是渭河谷地河谷型城市儿童血铅与铅暴露最主要的贡献源,必须采取长期有效的监测与控制措施。     

城市内涝的时空分布特征及其成因分析 ——以呼和浩特市区为例

以呼和浩特市区为例,通过收集历史内涝数据与实地调查,共收集到78处积水点的具体位置、内涝范围和发生频率等实际数据,并对其内涝成因进行分析.结果表明:2016—2019年内涝灾害较2010—2016年频繁;其次,内涝主要发生在6—9月间,尤其集中在7月.空间分布特征表明,赛罕区积水点分布密度最大,而玉泉区最小.相关性分析...     

Environmental Equity and the Role of Public Policy: Experiences in the Rijnmond Region

This Φ Ψ study of environmental equity uses secondary quantitative data to analyze socioeconomic disparities in environmental conditions in the Rijnmond region of the Netherlands. The disparities of selected environmental indicators—exposure to traffic noise (road, rail, and air), NO₂, external safety risks, and the availability of public green space—are analyzed both separately and in combination. Not only exposures to environmental burdens (“bads”) were investigated, but also access to environmental benefits (“goods”). Additionally, we held interviews and reviewed documents to grasp the mechanisms underlying the environmental equity situation, with an emphasis on the role of public policy. Environmental equity is not a priority in public policy for the greater Rotterdam region known as the Rijnmond region, yet environmental standards have been established to provide a minimum environmental quality to all local residents. In general, environmental quality has improved in this region, and the accumulation of negative environmental outcomes (“bads”) has been limited. However, environmental standards for road traffic noise and NO₂ are being exceeded, probably because of the pressure on space and the traffic intensity. We found an association of environmental “bads” with income for rail traffic noise and availability of public green space. In the absence of regulation, positive environmental outcomes (“goods”) are mainly left up to market forces. Consequently, higher-income groups generally have more access to environmental “goods” than lower-income groups.     

Environmental Policy Beliefs of Stakeholders in Protected Area Management

Although the importance of understanding stakeholder beliefs regarding environmental policy has been noted by many authors, research focusing on the heterogeneity of stakeholder views is still very scarce and concentrated on a product-oriented definition of stakeholders. The aim of the present study is to address this gap by examining environmental policy beliefs of stakeholder groups engaged in protected area management. Questionnaires containing 73 five-point Likert scale items were administered to eight different stakeholder groups involved in the management of Greek protected areas. Items referred to core beliefs on environmental policy, namely, the value framework and sustainable development, and secondary beliefs, that is, beliefs on social consensus and ecotourism development. Our study used as a starting point respondent recruitment on the basis of a traditional product-centered approach. We investigated whether environmental policy beliefs can be used to effectively segregate stakeholders in well-defined segments, which override the product-oriented definition of stakeholders. Indeed, K-means clustering revealed an innovation-introduction and an implementation-charged sample segment. The instrument utilized in this research proved quite reliable and valid in measuring stakeholder environmental policy beliefs. Furthermore, the methodology implied that stakeholder groups differ in a significant number of belief-system elements. On the other hand, stakeholder groups were effectively distinguished on a small set of both core and secondary beliefs. Therefore, the instrument used can be an effective tool for determining and monitoring environmental policy beliefs of stakeholders in protected area management. This is of considerable importance in the Greek case, given the recent establishment of 27 administrative bodies of protected areas, all of which are required to incorporate public consultation into management practices.