Historical record of black carbon in urban soils and its environmental implications

Energy use in urbanization has fundamentally changed the pattern and fluxes of carbon cycling, which has global and local environmental impacts. Here we have investigated organic carbon (OC) and black carbon (BC) in six soil profiles from two contrast zones in an ancient city (Nanjing) in China. BC in soils was widely variable, from 0.22 to 32.19 g kg⁻¹. Its average concentration in an ancient residential area (Zone 1) was, 0.91 g kg⁻¹, whereas in Zone 2, an industrial and commercial area, the figure was 8.62 g kg⁻¹. The ratio of BC/OC ranged from 0.06 to 1.29 in soil profiles, with an average of 0.29. The vertical distribution of BC in soil is suggested to reflect the history of BC formation from burning of biomass and/or fossil fuel. BC in the surface layer of soils was mainly from traffic emission (especially from diesel vehicles). In contrast, in cultural layers BC was formed from historical coal use. The contents of BC and the ratio of BC/OC may reflect different human activities and pollution sources in the contrasting urban zones. In addition, the significant correlation of heavy metals (Cu, Pb, and Zn) with BC contents in some culture layers suggests the sorption of the metals by BC or their coexistence resulted from the coal-involved smelting.     

Valuation of open space and conservation features in residential subdivisions

Conservation subdivision design has been promoted as a way to protect ecologically sensitive areas while maintaining housing densities comparable to standard subdivisions, but many developers and planners question the appeal of conservation design to consumers. This study was conducted to compare economic aspects of conservation subdivision design to standard subdivision design in the midwestern United States. Three methods were used to determine the value homebuyers have for embedded conservation features in residential areas: transactional analyses (to indicate the value homebuyers have expressed for such features in the past); hedonic analyses (to determine the proportion of present value of homes attributable to such features); and contingent valuation (to examine willingness to pay according to homebuyers' preferred features, an indicator of potential future investment). Transactional analyses were based on assessment and transaction data for homes in three conservation-oriented subdivisions and three standard subdivisions in Cedar Rapids, Iowa, United States. Hedonic price models were also derived from assessment and transaction data. Contingent valuation analyses were based on a survey of residents in the same six subdivisions. Transactional data indicated higher 5-year appreciation rates for conservation versus standard subdivision design. Hedonic price models revealed that well-integrated conservation features (e.g. protected stream corridors) within subdivisions have a positive effect on home prices. Sixty-six percent of all respondents indicated willingness to pay for more embedded open space. Maximum willingness to pay was related to several factors including income, gender, desired level of open space, and concern about urban development. Overall, these results indicate that consumer demand and willingness to pay for conservation subdivision design are positive and should not be considered a barrier to implementation.     

Accumulation of Cs in puddle sediments within urban ecosystem

The role of puddle sediments as a final depot of ¹³⁷Cs horizontal migration within the urban landscape is studied using the example of Ekaterinburg city, Russia. Radioactive contamination in the city appeared due to fallout after atmospheric testing of nuclear weapons and nuclear accidents. Contamination density of ¹³⁷Cs in the region was assessed from archive data to be about 5.1 kBq/m², of which the maximum activity concentration (<30 Bq/kg) is associated with the upper 15 cm soil layer. Results of the survey reported here indicate a mean ¹³⁷Cs activity concentration in puddle sediments of 80 Bq/kg, with a maximum value of 540 Bq/kg. It is estimated that horizontal migration has led to about a fourfold concentration of ¹³⁷Cs in puddle sediments.     

长江经济带城市发展绿色效率研究

我国经济发展进入新常态,资源和环境约束压力不断增强。城市是现代经济增长的中心,绿色高效是我国城市转型发展的必由之路。本文构建反映城市经济增长、社会效益、资源节约、环境保护的绿色效率体系,并利用DEA作为工具来监测长江经济带108个地级及以上城市绿色效率。研究表明,长江经济带城市绿色效率整体水平不高,但是有逐步改善的趋势。将城市绿色综合效率进一步分解为规模效率和技术效率,相比规模效率,技术效率成为制约长江经济带绿色城市综合效率的主要因素。长江经济带城市要改变目前效率低下的现状关键在于提高技术效率,推进城市的创新发展,推动新技术、新产业、新业态的发展,促进产业结构的优化升级。本文对投入产出的冗余度与不足度进行了分析,并解释了低效率的根源。从资源投入的冗余度来看,土地资源能源劳动力技术资本水资源,长江经济带资源利用率低,存在高投入、高消耗的问题,加快长江经济带中西部地区城市绿色发展,应合理配置资源要素。从期望产出不足度来看,地方财政预算内收入社会消费品零售总额GDP,长江经济带目前总体发展模式还是追求经济产出的最大化,而忽视了经济运行的质量与社会效益。绿色效率不高主要集中在资源的过度消耗和环境污染物过度排放方面,其中环境问题成为城市发展过程中提高绿色效率亟待解决的重点和难点问题。应共同推进生态环境的保护,改革创新环境管理体制机制,推行环境保护市场化,加强对环境的监管和治理,这关系着长江经济带城市发展绿色效率的提高与生态文明示范带的实现。     

丝绸之路经济带环保投资效应研究

丝绸之路经济带建设是我国的重大战略决策,但是脆弱的生态环境制约了该区域的可持续发展。环保投资能够实现经济与环境的双赢,是复兴丝绸之路经济繁荣和生态文明的重要推手。为了解丝绸之路经济带的环保投资效应,进而提供优化丝绸之路经济带环保投资的决策支持,本文应用2004-2011年丝绸之路经济带9省市的数据,构建面板效应模型,测度丝绸之路经济带环保投资总额及投资分项的经济与环境效应。其中,环境污染治理投资总额以及三种环保投资分项(即建设项目"三同时"投资、工业污染源治理投资、城市环境基础设施建设投资)是自变量;表征经济发展总量、结构、就业的5项指标和表征环境质量的资源利用、污染排放的5项指标是因变量。研究发现,丝绸之路经济带的环保投资能够有效带动该区域的经济总量增长、经济结构优化、就业水平提升,同时有助于该区域提升资源利用效率、降低污染排放;三类环保投资分项的经济与环境效应中,城市环境基础设施建设投资起主导作用,工业污染源治理投资效应最差;丝绸之路经济带9省市的环保投资效应相差较大,其中四川省环保投资效应最优。虽然丝绸之路经济带的环保投资已取得一定成效,但是仍存在以下问题:其一,环保投资总量不足,尚未达到环境质量改善所需的国际标准;其二,环保投资结构不合理,即环保投资过于集中在城市环境基础设施建设上,工业污染治理投资相对较弱;其三,环保投资流向不恰当,表现为环保投资对就业水平提升、产业高级化、能耗控制、固废处置的作用不明显。针对丝绸之路经济带环保投资的现存问题,本文提出以下建议:通过政府环保支出引导社会资金流入环保市场,进而加大丝绸之路经济带的环保投资力度;调整环保投资分项比例,将环保投资向工业污染源治理转移;改善环保投资流向,使其促进环保产业发展、推动清洁能源使用、提升工业固废和生活垃圾综合利用能力等。     

基于环境效率评价的成渝经济区产业结构与布局优化

优化、高效的产业结构及布局是区域经济社会环境全面发展的必备条件。借用区位商的指标设计理念,尝试性地提出了产业环境商和区域环境商的概念和计算公式,并以此为基础对成渝经济区的产业结构及空间布局进行了优化,为基于区域资源禀赋、产业基础、产业竞争力等经济社会指标优化产业结构和空间布局的传统范式加入了新视角和新方法,也为环保部门参与综合决策提供了新的理论支撑。从缓解酸雨问题入手,基于各行业SO2排放的区域环境商和产业环境商测算结果,对成渝经济区产业结构进行了优化。在此基础上,以造纸业为例,基于各地市SO2排放的区域环境商的测算结果,结合各地市SO2的可增排量和造纸业的产业发展现状,对成渝经济区造纸业的空间布局进行了优化     

皖江城市带温泉旅游地定量评价及开发策略

运用专家咨询法,从温泉资源质量、市场区位条件、区域支持条件3个方面构建了涵盖13个评价因子的温泉型旅游地开发评价指标体系。为最大限度降低评价的主观性,将评价因子分为数值型和模糊型两种,综合运用菲什拜因 罗森伯格模型和模糊数学模型,在深入调研皖江城市带各温泉旅游地并掌握相关数据的基础上,从市域层面对皖江城市带6个地区的温泉旅游开发条件进行了量化评价。结果显示: 合肥、马鞍山开发条件最优,其温泉旅游资源与市场区位及区域支持条件匹配良好;安庆、六安次之,宣城、池州较差。最后结合评价结论,先从文化和竞合2个方面提出皖江城市带温泉旅游地整体开发和提升的策略,再针对得分不同地区的开发现状和所处阶段,分别提出“共生模式”和“提升模式”两大对策     

近百年重庆主城区汛期降水及其集中期的变化特征

利用一种改进的定义汛期降水集中期的方法对重庆主城区近百余年汛期降水集中期进行了划分,并分析了集中期的重心日、雨量及其与汛期降水总量的关系。结果表明：近百余年重庆主城区汛期降水量线性变化趋势不明显,阶段变化显著。百余年来发生过两次突变,分别发生于1914年和1925年,分别突变为增加和减少趋势。3 a左右的周期为汛期降水的主要周期。6月为降水集中期重心日发生最多的月份,8月出现相对较少,4月上半月和10月均没有出现过。近百余年重庆主城区降水集中期雨量及其占汛期降水总量的比例表现为线性增加的趋势,它们的阶段性变化比较一致,尤其是21世纪以来近10 a显著偏多。集中期雨量与汛期降水之间存在很好的相关关系,但是在某些特殊年份上也存在差异。15 d滑动统计方法划分的集中期雨量作为一种极端气候事件,具有较强描述灾害事件的能力,但其极端特殊性可能会表现在某些特殊年份或年际间的变化中,充分认识其规律,能为诊断和预测业务提供更为可靠的参考依据     

皖江城市群旅游经济空间联系格局

在皖江城市群作为承接长三角产业转移示范区背景下及区域交通网络化、区域旅游一体化发展的新形式下,对皖江城市群旅游经济联系和影响范围研究就显得必要。以该地区10城市的旅游经济联系为主线,以界定旅游中心节点、测算旅游经济联系量和场强模型为手段,构建皖江城市群旅游圈。研究表明：以合肥和芜湖为双核的皖江城市群大旅游圈,其内部分为3个次旅游经济圈,北部以合肥为中心,包括六安区域、滁州和含巢湖整个水面的大部分区域的合肥旅游圈;西南以安庆为中心、池州为副中心,含铜陵一部分地区的安庆旅游圈;东南以芜湖为中心、宣城为副中心,包括马鞍山和部分巢湖区域、部分铜陵区域的芜湖旅游圈。最后提出了3个旅游经济圈发展的旅游规划建议     

Multifaceted Value Profiles of Forest Owner Categories in South Sweden: The River Helge å Catchment as a Case Study

Forest landscapes provide benefits from a wide range of goods, function and intangible values. But what are different forest owner categories’ profiles of economic use and non-use values? This study focuses on the complex forest ownership pattern of the River Helge å catchment including the Kristianstad Vattenrike Biosphere Reserve in southern Sweden. We made 89 telephone interviews with informants representing the four main forest owner categories. Our mapping included consumptive and non-consumptive direct use values, indirect use values, and non-use values such as natural and cultural heritage. While the value profiles of non-industrial forest land owners and municipalities included all value categories, the forest companies focused on wood production, and the Swedish Environmental Protection Agency on nature protection. We discuss the challenges of communicating different forest owners’ economic value profiles among stakeholders, the need for a broader suite of forest management systems, and fora for collaborative planning.

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