太湖藻型湖区CH4、CO2排放特征及其影响因素分析

为明确太湖藻型湖区温室气体CH_4、CO_2排放特征及其影响因素,本研究利用便携式温室气体分析仪改进的静态箱法,对太湖梅梁湾春、夏季的CH_4、CO_2通量进行观测,并分析其影响要素.主要结果为:观测地点春、夏季CH_4、CO_2通量具有明显日变化动态.春季,CH_4通量白天大于夜间,夏季夜间大于白天;春、夏季,CO_2吸收通量均白天大于夜间.梅梁湾藻型湖区春、夏季为CH_4源,且CH_4释放通量在夏季明显高于春季,春、夏季的平均通量分别为4.047 nmol·(m~2·s)~(-1)和40.779 nmol·(m~2·s)~(-1);该区域春、夏季为CO_2汇,且春季CO_2吸收大于夏季,春、夏季的平均通量分别为-0.160μmol·(m~2·s)~(-1)和-0.033μmol·(m~2·s)~(-1).在小时尺度上,CH_4释放通量与气温和水温呈显著正相关(r=0.20,P0.01;r=0.34,P0.01),当风速6 m·s-1时,与风速呈显著正相关(r=0.71,P0.01);CO_2吸收通量与气温和风速呈显著正相关(r=0.14,P0.01;r=0.33,P0.05),与气压和太阳辐射呈显著负相关(r=-0.41,P0.01;r=-0.35,P0.01);CO_2释放通量与风速呈显著正相关(r=0.40,P0.05),与太阳辐射呈显著负相关(r=-0.35,P0.01).在日尺度上,CH_4释放通量与水温和气温呈显著正相关(r=0.83,P0.01;r=0.78,P0.01).     

Spatial and Temporal Distribution of Norovirus and <Emphasis Type="Italic">E. coli</Emphasis> in Sydney Rock Oysters Following a Sewage Overflow into an Estuary

This paper reports a study of norovirus (NoV) GII distribution and persistence in Sydney rock oysters (SRO) (Saccostrea glomerata) located in an estuary after a pump station sewage overflow. SRO were strategically placed at six sites spanning the length of the estuary from the pump station to the sea. The spatial and temporal distribution of NoV, hepatitis A virus (HAV) and Escherichia coli (E. coli) in oysters was mapped after the contamination event. NoV GI and GII, HAV and E. coli were quantified for up to 48 days in oysters placed at six sites ranging from 0.05 to 8.20 km from the sewage overflow. NoV GII was detected up to 5.29 km downstream and persisted in oysters for 42 days at the site closest to the overflow. NoV GII concentrations decreased significantly over time; a reduction rate of 8.5% per day was observed in oysters (p < 0.001). NoV GII concentrations decreased significantly as a function of distance at a rate of 5.8% per km (p < 0.001) and the decline in E. coli concentration with distance was 20.1% per km (p < 0.001). HAV and NoV GI were not detected. A comparison of NoV GII reduction rates from oysters over time, as observed in this study and other published research, collectively suggest that GII reduction rates from oysters may be broadly similar, regardless of environmental conditions, oyster species and genotype.     

Trends in spatial and temporal levels of persistent organic pollutants in Lake Erie sediments

A Lake Erie sediment survey was conducted in 1997 to characterize spatial trends in contamination, and for comparison with a 1971 survey to assess any changes in environmental quality since the advent of measures to reduce contaminant sources. Contaminant data for some contaminant classes in 1971 was based on analysis of frozen archived samples, thereby allowing a direct comparison between surficial sediment contamination in 1971 and 1997 based on modern analytical methods. Lake-wide contaminant concentrations of polychlorinated biphenyls (PCBs) and organochlorine compounds including hexachlorobenzene and the DDT compounds in 1997 were substantially lower, compared to levels in samples collected in 1971. Lake-wide average sediment PCB levels were found to have decreased roughly 70% from 136 ng/g in 1971 to 43 ng/g in 1997. Similarly, reductions in other compound classes ranged from 40% to 80%. In 1997, some individual contaminants classes including PCBs exhibited a spatial trend toward increasing sediment contamination from the eastern basin to the western basin, and from the north-central basin to the south-central basin. Levels of organic contaminants in sediments in some areas of Lake Erie still exceeded the strictest Canadian Federal and Ontario Provincial guidelines. However, exceedances of guidelines describing contaminated environments in 1997 were predominantly restricted to the western basin and near-shore sites in the southern part of the central basin.     

环境样品中多氯联苯分析的新进展

综述了环境中多氯联苯（ＰＣＢｓ）分析方法的新进展，阐述液液，液固萃取，精制富集待测物，色谱，色／质鉴定，对多维气相色谱改进ＰＣＢｓ分离，色谱／富里叶红外，保留指数区分ＰＣＢｓ异构件进行讨论。     

大气优化布点监测方法简化试验

将每天TSP、SO_2两种污染物各采四次样并分别进行测定,简化为每天各采一个“日混合样”进行测定,对测定结果进行数理统计检验结果表明:测定值之间不存在显著性差异、两种方法的测值波动是由偶然因素造成的,因此,简化方法即采日混合样进行分析是一种可靠的监测方法,它适用于煤质中含硫份较低的地区。     

吹扫捕集/气相色谱法测定空气中挥发性有机物

研究并建立了用吹扫捕集气相色谱法测定空气中挥发性有机物的分析方法。以空气中苯系物为目标化合物,以静态法配制标准气体,分别作了高、中、低三种浓度的标准曲线,其相关系数在0 98以上。该法对空气中苯系物的方法检出限为0 14～0 16μg m3,相对标准偏差在2 1%～6 3%之间,回收率在92%～120%。     

One independent variable rate equation describing utilization of biodegradable organic matter in activated sludge processes

This investigation aims to represent aerobic utilization of biodegradable organic matter present in wastewater by a rate equation. This rate equation can then be used to develop a substrate utilization (removal) kinetic model for unsteady state activated sludge process. To achieve this objective, theoretical utilization of biodegradable organic matter in batch process and growth pattern theory were studied. Also, experimental data representing removal of organic matter in different types of wastewaters were collected and analyzed for batch and continuous activated sludge assays. A rate equation was proposed to describe the utilization of biodegradable organic matter based on theoretical analysis of batch process. This rate equation was then verified through differential and integral analysis of the experimental data. Furthermore, a substrate kinetic model for batch and continuous processes was developed. The developed rate equation will facilitate the analysis and design of sequencing batch reactor (SBR) technology for biological treatment of wastewater.     

基于主成分分析法对安肇新河水质评价的研究

安肇新河为大庆市的南线排水系统的主要排水干渠.安肇新河河道北起王花泡滞洪区,南抵松花汪,东邻肇兰新河,西至大庆市西排干,流域形状基本上为狭长形,河道的主要任务是排泄古恰闸以上七个滞洪区及各区间的来水.由于运用单因子综合评价法无法对安肇新河的水质进行比较分析,特引入主成分分析法对近十年数据进行分析,进一步比较了安肇新河时间和空间上的水质变化情况.通过对因子选择和计算,对安肇新河近10年的数据进行空间和时间的科学比对,进行综合比较并作出时间和空间上的评价.     

危险化学品环境风险评估报告编制中若干问题的研究

为加强重点危险化学品环境管理工作,国家要求实行重点危险化学品环境风险评估制度。在风评制度尚未全面开展的情况下,通过先行对一家重点环境管理危险化学品使用企业开展风险评估,从而对风评报告编制过程中存在的问题与困难进行总结,并提出建议与对策,可为其他编制机构开展环境风险评估工作提供指导作用。     

区域次生环境风险评价方法研究

针对化工园区内各装置次生环境风险进行了系统研究,建立了一套区域次生风险识别方法,并且以成品油储罐区和7万吨苯抽提装置为例对研究区燃爆类风险源和泄漏类风险源分别进行次生环境风险分析,识别化工园区内对环境有潜在威胁的风险源,结果表明：有8个危险源存在次生风险事故,且对可能发生的次生事故类型进行分析,为化工园区的次生环境风险的监控和防范提供了依据。