Effect of recent climate change on Arctic Pb pollution: a comparative study of historical records in lake and peat sediments

Historical changes of anthropogenic Pb pollution were reconstructed based on Pb concentrations and isotope ratios in lake and peat sediment profiles from Ny-?lesund of Arctic. The calculated excess Pb isotope ratios showed that Pb pollution largely came from west Europe and Russia. The peat profile clearly reflected the historical changes of atmospheric deposition of anthropogenic Pb into Ny-?lesund, and the result showed that anthropogenic Pb peaked at 1960s-1970s, and thereafter a significant recovery was observed by a rapid increase of (206)Pb/(207)Pb ratios and a remarkable decrease in anthropogenic Pb contents. In contrast to the peat record, the longer lake record showed relatively high anthropogenic Pb contents and a persistent decrease of (206)Pb/(207)Pb ratios within the uppermost samples, suggesting that climate-sensitive processes such as catchment erosion and meltwater runoff might have influenced the recent change of Pb pollution record in the High Arctic lake sediments.     

Distribution pattern of plant species diversity in the mountainous Region of Ili River Valley, Xinjiang

In this paper, detrended canonical correspondence analysis was performed to analyze the relationships between diversity indices and environmental gradients, generalized additive model was employed to modal the response curves of diversity indices to the elevation, based on data from field investigation in the mountainous region of the Ili River Valley and a survey of 94 sample plots. Two hundred fifty-nine plant species were recorded in the 94 sample plots investigated, up to 235 species all appeared in the herb layer, and the species of woody plants were very limited. The communities with a complicated vertical structure presented higher values of indices. The distribution pattern of plant species diversity on the northern slope was affected by such factors as elevation, slope aspect, slope gradient, total nitrogen, total potassium, soil water content, organic matter, and that on the southern slope was mainly affected by such factors as slope gradient, elevation, available phosphorus, and soil water content. On the northern slope, Patrick index and Shannon?CWiener index of the plant communities presented a bimodality pattern along altitude; Simpson index and Pielou index showed a partially unimodal pattern. On the southern slope all the distribution pattern of species diversity indices showed two peaks, though Patrick index??s bimodality pattern was not an obvious one. These altitudinal patterns were formed by the synthetic action of a variety of environmental factors with elevation playing an important role.     

医院用汞对市政污水中汞的贡献

对经市政管网排入高碑店污水处理厂的医疗行业污水进行汞来源的调查研究.根据抽样定律确定了医院采样点的数量和位置,利用原子荧光光度计测定采样点的汞含量,并根据采样点的排水量计算采样点的汞排放量.利用线性回归的方法建立汞排放量与医院床位数和门诊量的线性模型.结果表明:高碑店流域医疗行业汞排放总量为58.27 g/d,对高碑店污水处理厂进水汞的贡献率为5.48%,表明医疗行业对于高碑店污水处理厂进水汞的贡献并不是主要因素,要进行市政污水中汞来源的全面调查,必须对其他行业进行深入研究.对医院行业污水汞的减排提出了对策和建议.      

上海大气颗粒物中六溴环十二烷的污染特征及人体呼吸暴露水平

利用液相色谱-串联质谱研究了2008年上海市全年大气颗粒物中六溴环十二烷(HBCDs)的污染水平和异构体组成特征,在此基础上进一步运用风险商评估了上海市人群每日通过大气吸入HBCDs的非致癌风险.结果表明,城郊采样点宝山(BS)大气颗粒物中HBCDs的年平均浓度为30.20 pg·m-3,城区采样点徐家汇(XJH)大气颗粒物中HBCDs的年平均浓度为18.55 pg·m~(-3),城郊采样点的浓度显著高于城区采样点(p0.01);与国内外其它研究区域相比,上海大气中HBCDs的污染总体处于较低水平;上海市大气颗粒物中HBCDs异构体组成与工业品中HBCDs的组成呈现出明显差异,α-HBCD的比例显著升高,发生了异构体转化;上海市人群每日呼吸暴露剂量远低于文献中的参考值,非致癌风险商(HQ)介于10~(-4)~10~(-5)之间,非致癌健康风险较小,表明在上海市大气颗粒物中HBCDs的呼吸暴露为低风险.     

论多中心环境行政范式的建立与温州模式的拓展研究

以温州模式为媒介,探讨多中心环境行政范式建立及环保与经济一体化构建问题,并从环境立法及环境管理视角研究温州经济与环保双赢范式,以求打破以往温州模式研究视角与领域的桎梏,也为建构和谐社会提供一个视角。     

中国绿色消费的政策和实践研究

我国政府高度重视绿色消费,绿色消费政策框架的雏形已初步显现。随着各级政府相关政策的出台,对政策系统梳理,以及对政策的落实情况和实施效果进行评估具有重要的学术价值和现实意义。基于层次梳理法,从中央政策、国务院政策和部门政策三个“战略层面”,以及部门政策中具备“经济类”和“信息化工具类”属性的两个“目标层面”,结合政策的功能作用和市场认可程度将部门政策细分到“实施层面”,梳理得出我国绿色消费政策框架。通过分析我国绿色消费政策的分布情况和特点,对绿色消费政策与国家统计局的居民消费支出分类进行对比分析。同时,本文对我国已经实施的各类政策效果进行评估,分析目前我国绿色消费政策和实践面临的挑战,提出相关政策建议。     

国际化学品安全管理的现状及发展趋势

充分分析了国际化学品安全管理的现状,在此基础上,详细阐述了国际化学品安全管理的六大发展趋势:国际化的化学品风险评估体系将逐步扩展和深化;化学品分类和标识的全球统一系统(GHS)将逐步建立和完善;有毒化学品及其风险的信息交换将日益加强;减低风险计划将逐步完善和实施;利用国际援助加强国家化学品管理能力建设将越来越广泛;有毒有害化学品的国际非法交易将得到有效禁止。其中建立国际化的化学品安全管理模式、强调各国之间的信息交换和有效配合是化学品安全管理的主要趋势。另外,文中还论述了我国在化学品安全管理方面所存在的薄弱环节,必须制定应对策略加以强化和完善。      

边坡稳定性影响因素敏感性灰色关联分析

提出采用灰色系统理论中的灰色关联分析方法对边坡稳定进行敏感性分析,通过建立起边坡的灰关联数据矩阵,并采用极差变化对数据矩阵进行无量纲化处理,可计算出敏感因子变化与边坡安全系数之间的灰关联系数和灰关联度,从而确定出边坡稳定的敏感因素。结合福建某边坡加固工程实例,针对土体容重、粘聚力、内摩擦角、地下水位、坡高、坡率等影响因素,对该边坡稳定性进行了单因素的敏感性分析。结果表明,土体的内摩擦角、粘聚力是影响该边坡稳定性的主要敏感性因素,进而提出了有针对性的边坡加固措施。     

振动沉管灌注CFG桩的应用效果检测--以南京某工程为例

结合南京某工程地基处理实例,对振动沉管灌注CFG桩复合地基进行了现场试验和室内土工试验,通过对施工前后实验结果的分析和比较．结果表明地基承载力大幅度提高,桩间土加固效果较明显,CFG桩桩体作用明显．证明了振动沉管灌注CFG桩对饱和软土地基的处理方法是可行的。     

珠江三角洲地区典型菜地土壤与蔬菜重金属分布特征研究

通过对珠江三角洲地区的广州市、佛山市、江门市和惠州市典型菜地土壤和蔬菜中重金属（Pb、Cr、Cd、As和Hg）含量及其土壤中有效态（Pb、Cr、Cd）含量的调查,分析蔬菜重金属污染状况与土壤重金属含量的相关性,探讨了土壤重金属含量、有效态含量与土壤理化性质的相关性。结果表明,菜地土壤主要受Pb、Cd、Hg污染。Pb、Cd主要以轻度污染为主;而Hg污染在广州市菜地土壤以轻度污染和重度污染为主,佛山市菜地土壤以中度污染和重度污染为主,江门市和惠州市菜地土壤以轻度污染为主。蔬菜主要受Pb、Cd、Hg污染,少数蔬菜受到Cr污染,但并未检测出蔬菜受As污染。蔬菜中重金属含量与土壤中Pb、Cr、Cd的总量、有效态含量之间呈显著正相关关系,与土壤中As、Hg的总量无显著相关性。土壤中Pb、Cr含量与土壤有机质含量、黏粒含量、粉粒含量均达到显著相关。土壤中有效Pb与有效锰含量呈显著负相关关系,土壤中有效Cr含量与土壤粘粒含量、有效铁含量呈极显著正相关关系。