A GIS-based approach for the long-term prediction of human health risks at contaminated sites

A Health Index/Risk Evaluation Tool (HIRET) has been developed for the integration of risk assessment and spatial planning using GIS capabilities. The method is meant to assist decision makers and site owners in the evaluation of potential human health risk with respect to land use. Human health risk defined as the potential adverse effects on human life or health is generally accepted as the most important aspect for site assessment and planning of remediation strategies. It concerns polluted sites that endanger human health on one hand and derelict land that does not cause the immediate risk on the other hand. In current state-of-the-art risk-assessment, long-term spatial and temporal changes of risks, in relation to changes in contamination patterns and land use functions, are not taken into account. The aim of this paper is to demonstrate the methodology developed for human health risk assessment in aspect of spatial and temporal domain. HIRET was developed as an extension for ESRI software ArcView 3.2 and allows performing dynamic human health risk assessment in long-term period, which is relevant for land use planning. The paper illustrates how such methodology can assist in environmental decision-making to enhance the efficiency of contaminated land management. A case study of contaminated site is given showing how data can be used within a GIS framework to produce maps indicating areas of potential human health risk.     

麦田O3干沉降过程及不同沉降通道分配的模拟

利用涡度相关系统对南京地区冬小麦田和裸土期O₃干沉降过程进行观测的基础上,引入Surfatm-O₃干沉降模型,对其叶片气孔阻力（R_s^leaf）、土壤阻力（R_soil）和表面阻力（R_cut）的公式进行参数化修订和验证,开展了冬小麦主要生育期的总O₃通量（F_O3）、干沉降速率（V_d）及其不同沉降通道分配的模拟,并间接分析了土壤排放的NO与O₃的化学反应对O₃干沉降过程的影响.结果表明：冬小麦田F_O3和V_d的实测值与模拟值趋势相似,平均实测和模拟V_d值分别为0.39和0.37cm/s,模拟值比实测值低估5.3%,其中每一个独立阻力公式的模拟效果均较好.平均非气孔沉降（表面沉降和土壤沉降）是O₃干沉降主要的沉降通道,占总O₃通量的68.8%,表面沉降占非气孔沉降的46.7%;平均绿叶和黄叶气孔沉降分别占总O₃通量的28.6%和2.6%.白天非气孔沉降比例减小至占总O₃通量的58.8%,绿叶和黄叶的气孔沉降比例比值增大,分别占总O₃通量的37.7%和3.5%.夜晚表面沉降和土壤沉降分别占总O₃通量的64.3%和35.7%.土壤排放的NO会与O₃产生化学反应,对O₃干沉降过程产生影响,需要在今后的O₃干沉降模型中考虑.     

Development and valuation of adaptation pathways for storm water management infrastructure

Policymakers today are faced with a difficult task of planning for large scale infrastructure that can cater to the climatic and socio-economic changes that the future will bring. To address the deeply uncertain nature resulting from long-term changes, it is becoming necessary to develop strategies that support flexibility and react more strategically than traditional planning approaches. This paper applies the concept of adaptation tipping points and adaptation pathways to a case study in Singapore for the planning of long-term urban drainage infrastructure. Using conventional grey and sustainable green solutions in isolation and in combination, adaptation pathway maps are developed and compared across outlined climatic and landuse scenarios. To understand and justify if the imparted flexibility is worth its cost, economic assessments are performed. This is a valuable extension of the existing framework, helps to identify the preferred configuration of land use and sub-select adaptation actions that should be implemented at the current time frame. The main finding of this study is that the adaptation pathways map for the sustainable grey landuse scenario economically outperforms those of the other outlined land uses. This provides a valuable insight for policy makers, as it implies that if carefully planned development is undertaken, the requirements of storm water management can be met in a sustainable manner, while simultaneously freeing up land for other purposes. This is especially important in the context of highly dense urban areas such as Singapore, where land is a scare resource.     

Degradation of tert-butyl formate and its intermediates by an ozone/UV process

In this paper, the oxidation of tert-butyl formate (TBF) in aqueous solution by an ozone/UV process was described. The oxidation process was investigated experimentally in a semibatch reactor. The results of the study indicated that the ozone/UV process was very effective in oxidizing TBF. tert-Butyl alcohol (TBA), hydroxy-iso-butyraldehyde (HiBA), acetone, formaldehyde, and formic acid were identified as major primary intermediates during the oxidation of TBF. About 90% organic carbon balance was obtained indicating that most reaction intermediates have been identified and quantified. Some of the primary intermediates were also oxidized in the ozone/UV system. Accordingly, HiBA, acetone, formaldehyde, and formic acid were the primary intermediates of TBA oxidation. The oxidation of acetone in the ozone/UV system generated formaldehyde, pyruvaldehyde, acetic acid, formic acid as primary intermediates. It was also observed that the reaction intermediates formed during the oxidation of TBF react well in the ozone/UV system and complete mineralization could be achieved by the process.     

环境雌激素生物效应的作用机制研究进展

环境雌激素(Environmental Estrogens, EEs)种类繁多、来源多样且分布广泛,大量工业添加剂、食品添加剂和农药类物质已被证实具有雌激素活性。EEs对人体生殖、神经、免疫等系统生物毒性,已经引起了公众的普遍关注。近年来的研究表明,EEs不仅可以结合雌激素核受体(nuclear Estrogen Receptor, nER)干扰正常的雌激素基因组信号通路,还能活化雌激素膜受体(membrane Estrogen Receptor, mER)引发快速的雌激素非基因组信号转导途径。本文总结了EEs通过nER、mER介导的多种雌激素基因组和非基因组信号途径及其产生的生物学效应,综述了在其毒理学作用机理基础上发展的环境样品的雌激素活性评估和EEs混合物的联合作用研究,以期为该类污染物的筛查、风险评估和进一步的机制研究提供参考。     

环境污染物导致氧化应激的关键信号通路及其检测方法

环境污染物能够以多种途径进入生物体内,在体内产生含氧自由基等活性氧物质,并通过多种信号通路及酶反应引起氧化应激,造成生物体内的脂质过氧化、蛋白质损伤、DNA表达改变、酶失活等,从而引发心血管疾病、风湿类疾病、感染及癌症等的发生。本文对环境污染物致氧化应激产生的原因、涉及的信号通路及酶反应、造成的危害,以及常见的基于细胞模型的氧化应激检测方法进行了综述,期望为评价环境污染物和检测氧化损伤提供参考。     

太湖不同水域沉积物甲烷释放潜力及其途径分析

为明确太湖不同湖区CH₄释放特征与释放潜力差异,采用水-气界面甲烷排放通量测定和室内厌氧培养,结合沉积物理化因子对太湖沉积物CH₄释放特征及其释放潜力差异进行研究。结果表明,不同湖区水-气界面CH₄排放通量存在显著差异;不同湖区、不同深度沉积物中CH₄释放潜力也存在明显差异,且CH₄释放潜力与含水率和总有机碳呈正相关,与盐度呈负相关;太湖沉积物产CH₄潜力最大的途径为甲基途径,且主要集中在沉积物10~35cm深度。由此可知,太湖是CH₄排放的净产生源,含水率、有机质和盐度等环境因子的差异以及沉积物深度均会影响沉积物甲烷排放和释放潜力,从而对太湖沉积系统的碳循环以及局部气候变化产生重要影响。     

水环境中抗生素的光降解研究进展

抗生素的大量使用已经成为了全球环境问题.由于其在环境水体中难以被微生物降解,且能导致细菌抗药性越来越受到关注.光降解是污染物在水环境中非常重要的非生物降解途径.本文介绍了水环境中抗生素的直接、间接和自敏化光降解动力学,着重阐述了抗生素的光降解过程的影响因素、降解产物和可能降解途径等最新研究成果,指出抗生素光降解产物的分离提取与结构鉴定,以及预测抗生素降解过程的动力学模型构建将成为今后主要的研究方向和趋势.     

Ecological network and emergy analysis of urban metabolic systems: Model development,and a case study of four Chinese cities

Analysis of the structure and function of urban metabolic systems is an important goal of urban research. We used network pathways and network utility analysis to analyze the basic network structure of the urban metabolic system and the complex ecological relationships within the system, providing a new way to perform such research. Using four Chinese cities as examples, we developed an ecological network model of the urban metabolic system. By using network pathway analysis, we studied the changing relationships between metabolic length and the number of metabolic pathways, and between metabolic length and reachability. Based on the distribution of the number of metabolic pathways, we describe the basic structure and intercompartment relationships of the system. By using the sign distribution in the network utility matrix, we determined the ecological relationships and degree of mutualism between the compartments of the system. The basic components of the system consisted of the internal environment, the external environment, and the agricultural, industrial, and domestic sectors. With increasing metabolic length, the ecological relationships among the components of the system became more diverse, and the numbers of metabolic paths and their reachability improved. Although the basic network structure of the four cities was identical, the mutualism index differed. Beijing's mutualism index was superior to that of Shanghai, and much higher than those of Tianjin and Chongqing. By analyzing the structure and function of the urban metabolic system, we provide suggestions for optimizing the structure and adjusting the relationships, and propose methods for the application of ecological network analysis in future urban system research.     

中国民航业中长期碳排放预测与技术减排潜力分析

基于LEAP构建自下而上的中国民航业能源系统模型,设置冻结、现有政策、力度、替代和革命五组情景,深入分析民航业的驱动因子和发展趋势,探讨中国民航业中长期低碳发展的技术路径.结果显示,预计2060年左右人均乘机次数翻两番,突破2人次,冻结情景下2060年会带来高达6.9亿t的碳排放.力度情景下,民航业碳排放有望在2044年左右达峰,峰值水平控制在3亿t左右,40年累积减排近50%,仅需增加约1万亿人民币的成本.稳步推进机队更新换代,加快基础设施提升和运营操作改进,发展可持续航空燃料是民航业必须依赖的减排手段,分别能带来44.1%、29.5%和26.4%的减排量.因此,民航业要尽早制定行业"双碳"目标和实施路径计划,中短期统筹推进空域改革、空中交通管理和航司精细化管理,大力支持国产大飞机的发展,长期推动可持续航空燃料全产业链商业化和市场化.