典型区域土壤中PCB-11的污染特征

利用高分辨气相色谱/高分辨质谱法研究了土壤中PCB-11（3,3＇-二氯联苯,CAS 2050-67-1）的污染特征和分布规律,探讨了土壤中PCB-11的污染来源.结果表明,我国一般城市地区（天津、鞍山）和电子垃圾拆解地周边土壤中PCB-11的检出率为100%,PCB-11可能广泛存在于土壤介质中.天津、鞍山、电子垃圾...     

秦皇岛近海养殖对潮间带微生物群落多样性的影响

潮间带微生物群落在驱动海岸带生态系统物质循环和能量流动中具有重要作用,近海养殖造成的环境问题日益凸显,但其对潮间带微生物群落结构的影响还缺乏研究。采用变性梯度凝胶电泳（DGGE）和限制性片段长度多态性（RFLP）的分子生物学技术,研究秦皇岛养殖区与旅游区潮间带沉积物中微生物多样性的差异,分析养殖区微生物的16S rRNA基因文库的组成特征。结果表明：养殖区的微生物群落结构与旅游区形成较大的差异,DGGE图谱中养殖区的特有条带主要集中于γ-变形菌纲（γ-proteobacteria）,还分布于α-变形菌纲（α-proteobacteria）,拟杆菌门（Bacteroidetes）,放线菌门（Actinobacteria）和厚壁菌门（Firmicutes）。影响潮间带微生物的群落结构的主要环境因子包括温度、盐度、pH和NO3-浓度,影响率达55.2%。对差异最大的洋河大桥南养殖区（Q1站）的微生物样品建立克隆文库分析群落结构,变形菌门（Proteobacteria）为优势菌群,占总群落的60%,其中γ-变形菌纲是主要存在的微生物纲,其余菌群包括放线菌门、拟杆菌门、蓝藻菌门（Cyanobacteria）和疣微菌门（Verrucomicrobia）的微生物。养殖区海岸带微生物群落中出现了与环境污染和赤潮密切相关的菌群,如拟杆菌门、肠杆菌属（Enterobacteriaceae）和α-变形细菌红细菌目（Roseovarius）的微生物。     

淮北市采煤塌陷区土壤养分状况

研究了淮北市采煤塌陷区内湿地(南湖湿地、东湖湿地)、园林绿地、耕地3种土地利用类型土壤的养分含量情况.结果显示:湿地中受人为干扰强烈的南湖湿地土壤全氮量为1.128g/kg,显著高于园林绿地,与人为干扰弱的东湖湿地和耕地无显著差异;湿地有机质含量南湖为23.781 g/kg,东湖为11.250 g/kg,二者之间无差异...     

胶州市农村地区地下水水质现状评价及保护措施

对胶州市农村地区地下水水质进行了监测分析,根据分析结果,利用单因子评价法和综合指数评价法,评价胶州市地下水污染程度。从评价结果可以看出,马店镇等乡镇水质较好,属清洁级;里岔镇等乡镇水质属轻污染级。通过查找原因,发现水质污染主要由农业面源、生活污水和畜禽养殖粪便所致,据此提出了建立污水集中处理厂,规范农村畜禽养殖行业和发展绿色农业等建议。     

论促进企业环境守法的制度建构

企业是市场经济中重要的市场主体,其环境守法除了要求环境法律、法规、政策的完善,也有赖于环境执法工作的稳妥开展对企业守法的推动。通过制度和利润两方面分析企业环境守法困境,期望通过环境执法模式的改革,借鉴美国环境执法模式的经验,借助执法理念的变化实现企业自觉的环境守法。     

土壤重金属污染的植物修复及超富集植物的研究进展

土壤重金属污染的植物修复是污染整治的重要手段之一。近年来对植物修复的研究日益增加,工业、农业和交通是土壤中污染物的三大主要来源。目前重金属污染土壤植物修复主要包括植物稳定、植物提取和植物挥发。由于超富集植物存在生物量小、生长缓慢的缺点,更应该关注具有高生物量的重金属耐(抗)性植物。     

铜矿尾矿污染的综合治理

对铜矿选矿过程中产生的尾矿浆进行机械压滤,滤水循环利用,尾矿渣用于制砖,实现选矿废水、废渣零排放。一直困绕着铜矿选矿的尾矿污染难题被攻破     

Comparison of receptor models for source apportionment of volatile organic compounds in Beijing, China

Identifying the sources of volatile organic compounds (VOCs) is key to reducing ground-level ozone and secondary organic aerosols (SOAs). Several receptor models have been developed to apportion sources, but an intercomparison of these models had not been performed for VOCs in China. In the present study, we compared VOC sources based on chemical mass balance (CMB), UNMIX, and positive matrix factorization (PMF) models. Gasoline-related sources, petrochemical production, and liquefied petroleum gas (LPG) were identified by all three models as the major contributors, with UNMIX and PMF producing quite similar results. The contributions of gasoline-related sources and LPG estimated by the CMB model were higher, and petrochemical emissions were lower than in the UNMIX and PMF results, possibly because the VOC profiles used in the CMB model were for fresh emissions and the profiles extracted from ambient measurements by the two-factor analysis models were "aged".     

Application of a magnetotactic bacterium, Stenotrophomonas sp. to the removal of Au(III) from contaminated wastewater with a magnetic separator

In this study, the feasibility of applying a magnetotactic bacterial isolate (MTB), Stenotrophomonas sp. to the removal of Au(III) was investigated. Biosorption experiments showed that Au(III) biosorption capacity exhibited no significant difference in the initial pH range of 1.0-5.5, while decreased more significantly in the initial pH range of 5.5-13.0. Langmuir isotherm indicated that the maximum Au(III) biosorption capacity of Stenotrophomonas sp. were 506, 369 and 308 mg g(-1) dry weight biomass at the initial pH values of 2.0, 7.0 and 12.0, respectively. Thiourea was proved to be an effective desorbent to recover Au from the MTB biomass and 91% Au adsorbed on the biomass could be recovered at equilibrium when the thiourea concentration was 0.8M. The magnetic separator developed by our research team used for separating Au loaded MTB biomass showed high separation efficiency, with 100% biomass removed at the magnetic intensity of 1200 Gs in 180 min. The analyses from FTIR and XRD further confirmed that the reduction of Au(III) to Au(0) by the reductants on the MTB biomass occurred, and the deposition of nano-crystal Au(0) particles, ranging from 24.7 to 31.4 nm, could be estimated on the biomass surface.     

Feasibility of phytoextraction to remediate cadmium and zinc contaminated soils

A Cd and Zn contaminated soil was mixed and equilibrated with an uncontaminated, but otherwise similar soil to establish a gradient in soil contamination levels. Growth of Thlaspi caerulescens (Ganges ecotype) significantly decreased the metal concentrations in soil solution. Plant uptake of Cd and Zn exceeded the decrease of the soluble metal concentrations by several orders of magnitude. Hence, desorption of metals must have occurred to maintain the soil solution concentrations. A coupled regression model was developed to describe the transfer of metals from soil to solution and plant shoots. This model was applied to estimate the phytoextraction duration required to decrease the soil Cd concentration from 10 to 0.5 mg kg⁻¹. A biomass production of 1 and 5 t dm ha⁻¹ yr⁻¹ yields a duration of 42 and 11 yr, respectively. Successful phytoextraction operations based on T. caerulescens require an increased biomass production.