湿式消解法对冷原子吸收测定生物样品中汞产生的干扰

用不同的湿式消解法对多种生物样品的进行消解测定,分析了实验的干扰因素,并推荐了比较适宜的消解方法。     

武江 (乐昌段)水体底泥重金属污染调查

对武江乐昌段由上游矿山废水排泄沟、中游霜降河和下游武江段3段水道底泥中Pb、Zn、Cu进行测定.结果表明,Pb的质量比为2.54×103 mg/kg、1.33×103 mg/kg和30.7 mg/kg,Zn的质量比为1.01×103 mg/kg、2.48×103 mg/kg和156 mg/kg,Cu的质量比为42.9 mg/kg、68.8 mg/kg和69.4 mg/kg.3段支水道底泥污染负荷指数(IPL值)分别是14.0、10.6和1.46,整个区域IPL值为6.19,达到极强度污染程度.Pb、Zn总体污染程度比Cu严重,对武江乐昌段及其下游地区存在潜在生态风险.指出,霜降河和废水排泄沟段底泥不能农用,需特别谨慎地疏浚、转运和处置,而武江段底泥则可农用.     

Analysis of a high PM10 episode observed at a coastal site nearby Shanghai, China

A high PM₁₀ episode observed at a coastal site nearby Shanghai during 18–19 January 2007 was analyzed in this study. The maximum hourly averaged PM₁₀ concentrations for the 2 days were 0.58 and 0.62 mg/m³, respectively. The meteorological condition during the episode was favorable for air pollution with large-scale stagnation. There was no dispersing effect by high wind, no scavenging function by precipitation, and no diluting process by clean marine air during the episode. The trajectories for 16–19 January all came from the northern region and kept in low levels, and during the episode peak time, from the morning of 18 to the morning of 19 January, trajectories all came from the northern inland areas and had passed over the coastal region of Jiangsu province before arriving at the site. The variation of the air pollution indexes (APIs) in the cities located in the upwind direction of the site during the episode days clearly shows a process of large-scale air pollution from north to south. The liner correlation coefficient for PM₁₀ and SO₂ concentrations is 0.774 during the episode, while for PM₁₀ and CO, it even reaches 0.995, which indicated that the high PM₁₀ was mainly emitted from the coal burning for domestic heating in winter. Therefore, the observed episode was caused by the transport of domestic heating pollutants accumulated in the boundary layer from northern continental areas.     

常见拟除虫菊酯和有机磷农药对鱼类的急性及其联合毒性研究

以崇明岛前卫村中心湖中鲫鱼、鲤鱼、鲢鱼及泥鳅作为实验动物.进行了氯氰菊酯(原药和商品)、氰戊菊酯(原药和商品)、毒死蜱(原药和商品)、甲氰菊酯(商品)、溴氰菊酯(商品)、辛硫磷(商品)以及乙酰甲胺磷(商品)7种供试农药对实验鱼种的急性毒性及联合毒性实验,并检测了前卫村中心湖水体中18种有机磷农药和4种拟除虫菊酯农药,其中检出了1种有机磷农药(毒死蜱)和3种拟除虫菊酯农药(氰戊菊酯、氯氰菊酯、甲氰菊酯).结果表明,在单一农药急性毒性实验中,鲤鱼对供试农药表现较敏感,其次是鲫鱼和鲢鱼,而泥鳅对农药的耐药性最强;7种供试农药中,拟除虫菊酯农药相对于有机磷农药表现出较高的急性毒性,其实验鱼种的半数致死浓度(LC60)皆在μg/L级;对拟除虫菊酯农药(氯氰菊酯,氰戊菊酯)与有机磷农药(辛硫磷、乙酰甲胺磷)进行的联合毒性实验结果表明,除了暴露时间为24、48 h时氰戊菊酯与辛硫磷混配对鲢鱼的毒性实验表现为协同作用外,其余皆为拈抗作用.     

杭州市区大气能见度变化趋势及其与主要污染物相关性分析

利用2004-2006年地面气象观测资料和同期环境空气质量自动监测数据,分析了杭州市区大气能见度变化趋势及其与主要污染物的相关性.结果表明,杭州市区能见度的日分布特征为14时最好,8时最差;季节变化特征为夏季>春季>秋季>冬季,全年仅7月能见度超过10 km;SO2、NO2、PM10浓度均随能见度增高而逐渐降低;影响能见度的首要因子为相对湿度和PM2.5,能见度与PM2.5浓度具有较好的相关性.     

基于模糊数学的贡嘎山景区燕子沟景群旅游开发项目环境质量评价

应用模糊综合评价的方法进行环境质量评价,能较传统方法提供更多信息。本文将模糊数学的方法首次应用于贡嘎山景区燕子沟景群区环境质量综合评价,选择线性模糊分布确定隶属函数,并采用标准加权法计算权重因子,以消除评价因子实测浓度的影响。分别采用两类算子模型进行评价,结果均表明评价区总体环境质量属于清洁型。     

Metals Associated with Suspended Sediments in Lakes Erie and Ontario, 2000–2002

Sediment traps were deployed in the three major basins of Lake Erie, and the central (Mississauga) basin of Lake Ontario, and refurbished seasonally over the period 2000–2002. In Lake Ontario, sediment down-flux rates and corresponding contaminant down-flux rates were highest in winter during periods of unstratified thermal conditions, and generally increased with depth due to the influence of resuspended bottom sediments during all sampling periods. Lake Ontario suspended sediments exhibited the highest concentrations of metals; concentrations of mercury and lead frequently exceeded guideline values for bottom sediments. Contaminant levels in Lake Ontario suspended sediments were similar to concentrations in bottom sediments in the same area. There was a spatial trend toward higher suspended sediment metals concentrations from the eastern basin to the western basin of Lake Erie, which is similar to the trend in bottom sediment contamination. In the eastern basin of Lake Erie, which is the deepest area of the lake, there was no trend in down-flux rate with depth in 2001; however, down-flux rates increased with depth in 2002. Suspended sediments in the western basin of Lake Erie were determined to be largely resuspended bottom sediments; all western basin samples collected in the study exceeded the guideline value for mercury (0.486 μg/g).     

磷浓度对海洋小球藻叶绿素荧光及生长的影响

海水富营养化影响微藻生长,引起海洋初级生产力变化.以海洋小球藻(Chlorella sp.)为研究对象,研究不同磷浓度对其叶绿素荧光、细胞密度和色素含量变化的影响,以期找到海洋小球藻最适生长的磷浓度,为富营养条件下微藻生长的研究提供基础资料.结果表明,在培养温度为(22±1) ℃、光照强度为4 000 lx、光暗比为12 h:12 h条件下,不同磷浓度对海洋小球藻叶绿素荧光、细胞密度及色素含量影响显著,最大光能转化效率(Fv/Fm)、潜在活性(Fv/Fo)、实际光能转化效率(ΦPSⅡ)和电子传递速率(ETR)均呈先升后降的趋势,3.62 μmol/L处理组显著低于其他各组,434.52 μmol/L处理组一直处在较高水平.说明海洋小球藻的光合作用对高磷的适应范围较广,但对低磷浓度培养反应敏感.非光化学淬灭(qN)的值,3.62 μmol/L处理组高于其他各组.从细胞密度和色素含量的变化可以看出,36.21 μmol/L处理组最高,434.52、3.62 μmol/L处理组均低于36.21 μmol/L处理组.海洋小球藻生长的最适磷摩尔浓度为36.21 μmol/L.     

广东鲂幼鱼对铜、镉胁迫的氧化应激响应及其指示意义

广东鲂（Megalobrama terminalis）是具重要经济价值的珠江流域特有鱼类,已列入国家级水产种质资源保护品种。近年来,随着河流固有生境持续破坏,重金属等水体污染问题不断加剧,以广东鲂为代表的当地特有鱼类资源急剧下降。文章以铜、镉暴露对广东鲂幼鱼48 h的半致死浓度值LC50暴露浓度强度为1个毒性单位（TU）为基准,以室内静水实验法研究了铜、镉离子在低效应浓度、中效应浓度、高效应浓度（分别对应于0.01 TU、0.03 TU和0.11 TU）胁迫对广东鲂幼鱼的氧化应激效应,以期找出适宜的生物标记物,完善珠江水域污染评价与预警体系。结果显示,广东鲂幼鱼MDA、GSH、T-AOC、SOD和CAT（以Pr计）随暴露浓度及暴露时间发生变化,其范围分别在1.08~7.34 nmol·mg-1、0.42~22.82 mg·g-1、0.10~1.32 U·mg-1、2.45~13.24 U·mg-1和0.01~0.09 U·mg-1之间。其中,GSH、MDA和T-AOC在铜、镉暴露后第1天迅速响应至高值,相应的各浓度处理组明显高于对照组。曲线回归结果显示,GSH与暴露浓度c（以TU量计）之间呈显著的二次曲线关系,拟合方程为GSH=-2112（c-0.084）2＋18.1,r=0.847,n=10,P=0.012,暴露浓度阈值为0.084 TU。SOD和CAT则在暴露后第4天响应至高值。曲线回归结果显示, SOD 与 c 及 CAT 与 c 之间均呈显著的二次曲线关系,拟合方程分别为SOD=-2073（c-0.059）2＋14.3,r=0.840,n=10,P=0.014;CAT=-21.2（c-0.056）2＋0.102,r=0.877,n=10,P=0.006,相应的暴露浓度阈值分别为0.059 TU和0.056 TU。与暴露浓度呈显著的二次曲线关系的各指标中,GSH响应最为迅速,SOD和CAT的响应最为灵敏,加之SOD与CAT相关性极强,表明GSH、SOD和CAT这3种氧化应激指标可作为珠江流域水体污染的潜在生物标记物。     

长庆油田采出水处理系统污泥收集及处理

分析长庆油田采出水系统内污泥处理现状,介绍负压排泥和撬装离心脱水组合技术处理污泥的原理、流程及运行情况。该工艺流程在密闭状态下运行,占地少,污泥脱水率稳定,为油田采出水系统污泥处理技术发展和推广应用做了新的尝试。