长沙市乔口镇土壤重金属地球化学基线值的厘定及应用

随着工业化和城市化等人类活动影响的加强,土壤表层重金属含量趋于上升.作为区分自然背景和人为影响的指标,土壤重金属地球化学基线为土壤的污染评价提供了重要的参考依据.本研究以湖南省长沙市乔口镇为研究区域,利用标准化方法和累积频率曲线法两种方法,计算了这一区域土壤重金属的地球化学基线值,并利用富集因子来评价当地的重金属污染状态.结果表明,除极少数样品外,这一区域绝大多数样品并未受到明显的人为污染.乔口镇地处湘江下游,其地球化学基线值可以为长沙-株洲-湘潭(简称长-株-潭)经济区的土壤重金属污染提供参考.     

Managing the metropolitan environment: the challenge for European cities

Traditional approaches to metropolitan management have placed stress upon the achievement of physical and economic growth. In recent years attention has turned to environmental concerns and the achievement of sustainable urban development. It is important to define the objectives for the sustainable development of cities and to identify the principles upon which such development can be based.     

长株潭城市群推进绿色消费的政策重点与政策研究

长株潭城市群“两型社会”提倡从消费领域入手,以较少的资源消耗实现居民生活水平的提升,助推“两型社会”建设的良好作用机制。回顾了能源消费领域的研究进展,阐述了长株潭城市群推进绿色消费的背景,分析了长株潭城市群城乡居民日常消费现状与主要问题,在此基础上,提出了新时期长株潭城市群推进绿色消费的政策重点与政策建议,能够为“十三五”时期长株潭城市群绿色消费水平的提升提供一定的政策参考。     

长株潭城市群秋季大气颗粒物及其重金属元素污染特征

为研究长株潭城市群大气颗粒物及典型元素污染特征,于2011年11月在长沙、株洲、湘潭三地采集TSP和PM₁₀样品,同期在北京进行采样,以分析颗粒物及其中重金属元素(Cr、Cd、Hg、Pb和As)质量浓度的分布特征. 结果表明:秋季长沙、株洲、湘潭三地的ρ(TSP)均低于北京,背景点(长沙沙坪站)最低,为(110±48)μg/m3. 株洲ρ(PM₁₀)与北京相近,略高于湘潭和长沙,但背景点ρ(PM₁₀)仍为最低. ρ(PM₁₀)/ρ(TSP)在70.26%~95.80%之间,平均值为85.90%. 长株潭城市群的ρ(Cr)、ρ(Hg)、ρ(As)、ρ(Cd)和ρ(Pb)在TSP中分别为37.7~60.7、0.2~1.5、22.7~92.0、4.2~36.8和142.9~508.3ng/m3,在PM₁₀中相应分别为20.4~33.5、0.1~1.0、20.6~74.2、3.8~31.9和126.1~432.4ng/m3. 长株潭城市群各采样点Cd在TSP和PM₁₀中的富集因子均最大,分别为475.8~4690.7和840.5~7489.8;其次为Hg、Pb和As;Cr的富集因子在TSP和PM₁₀中分别为7.8~33.3和9.1~33.6,均为最小.      

基于压力-状态-响应模型的长株潭城市群生态承载力安全预警研究

在构建城市群生态承载力安全预警评价指标体系基础之上,通过数据的收集,利用灰色加权关联理论,计算了2006～2015年长株潭城市群生态承载力安全指数,并对各年份生态承载力安全警度进行了判定.计算结果显示:从总体来看,2006～2015年长株潭城市群生态承载力安全指数呈现出上升的趋势,安全警度由“高警”下降为“轻警”;从压力、状态、响应3个子系统来看,安全指数同样呈现出上升的趋势,安全警度则由“高警”或“中警”下降为“轻警”.分析表明:近些年长株潭城市群“两型社会”试验区相关资源与环境政策的实施效果是明显的.但我们也发现,试验区统计年份安全指数数值都在0.700 0之下,与“无警”(0.850 0)状态距之甚远,长株潭“两型社会”建设依然任重而道远.     

长株潭两型社会的生态市场培育研究

随着长株潭城市群两型社会建设的推进,培育生态市场经济已经成为必然要求。对长株潭两型社会生态市场发展面临的现状进行分析,研究了发展长株潭两型社会生态市场培育的要点与难点,最后借鉴国内外的相关经验,从法制保障、行政规制、经济手段、道德约束等方面,对长株潭两型社会的生态市场培育进行了分析与探讨。     

Private Sector Participation in Urban Water and Sanitation Provision in Ghana: Experiences from the Tamale Metropolitan Area (TMA)

African governments, like most countries in the developing world, face daunting tasks in their attempts to provide effective and equitable water and sanitation services for their ever increasing urban populations. Consequently, the past few years have witnessed increased private sector participation in urban water and sanitation provision, as many African governments strive to improve access to water and sanitation services for their citizens in line with Millennium Development Goal 7 (MDG7). Since the early 1990s, the government of Ghana and many local authorities have entered into various forms of public-private partnerships in urban water and sanitation provision. This article examines the outcome of such partnerships using the Tamale Metropolitan Area (TMA) as a case study with the aim of providing policy guidelines for the way forward. The article argues that the public-private arrangement for water supply and sanitation infrastructure management in the Tamale Metropolis has done nothing that an invigorated public sector could not have possibly achieved. It concludes that there can be no sustainable improvement in water and sanitation provision without political commitment, stakeholder ownership, and strong support for community driven initiatives.     

长株潭城市群人为源VOCs排放清单及其对环境的影响

基于长株潭城市群环境统计数据和排放系数,建立了2014年长株潭城市群人为源VOCs排放清单,并根据空间特征数据进行了3 km×3 km的空间网格分配,同时还估算了各类人为源排放VOCs的臭氧生成潜势与二次有机气溶胶生成潜势.结果表明,长株潭地区人为源VOCs排放总量为113.49 kt,其中工艺过程源、溶剂使用源和移动源为最主要的排放源,排放量分别为35.88、28.72、22.13 kt,工艺过程源中75.34%的VOCs排放量来自建材生产,溶剂使用源中建筑涂料和汽车喷涂为主要排放源;各区县中醴陵市的VOCs排放量最高为16.58 kt;长株潭地区总臭氧生成潜势为375.33 kt,溶剂使用源贡献最大为27.28%,生物质燃烧源的臭氧生成能力最强;二次有机气溶胶生成潜势中,溶剂使用源贡献比例最大为35.35%,其二次有机气溶胶生成能力也强于其它源类;空间分布特征显示城区的网格排放量较大.     

A transformative mission for prioritising nature in Australian cities

Australia is experiencing mounting pressures related to processes of urbanisation, biodiversity loss and climate change felt at large in cities. At the same time, it is cities that can take the leading role in pioneering approaches and solutions to respond to those coupling emergencies. In this perspective piece we respond to the following question: What are the required transformations for prioritising, valuing, maintaining and embracing nature in cities in Australia? We adopt the mission framework as an organising framework to present proposed pathways to transform Australian cities as nature-positive places of the future. We propose three interconnected pathways as starting actions to steer urban planning, policy and governance in Australian cities: First, cities need to establish evidence-based planning for nature in cities and mainstream new planning tools that safeguard and foreground urban nature. Second, collaborative planning needs to become a standard practice in cities and inclusive governance for nature in cities needs to prioritise Aboriginal knowledge systems and practices as well as look beyond what local governments can do. Third, for progressing to nature-positive cities, it is paramount to empower communities to innovate with nature across Australian cities. Whilst we focus on Australian cities, the lessons and pathways are broadly applicably globally and can inspire science-policy debates for the post COP15 biodiversity and COP26 climate change implementation processes.     

Municipal Solid Waste Management in the Accra Metropolitan Area, Ghana

Municipal solid waste management in Accra, Ghana, is at present delivered in an unsustainable manner. Due to uncontrolled urbanisation, large quantities of waste are generated daily in Accra, and this exerts much pressure on an over strained solid waste management system. Coupled with weak institutional capacity, and lack of resources, both human and capital, the city authorities face difficulties in ensuring that all the waste generated in the city is collected for disposal. Home collection of waste is limited to high and, some middle income areas while the poor are left to contend with the problem on their own. This leads to indiscriminate disposal of waste in surface drains, canals and streams, creating unsanitary, and unsightly environments in many parts of the city.