城市生态环境安全评价研究

城市作为一种典型的复合生态系统。其生态环境具有相当的脆弱性，因此如何改善生态质量和维护生态安全已成为城市发展要解决的主要问题之一。本文从生态环境状况和生态安全2个方面对张家港市生态环境安全进行评价和研究，计算了生物丰度指数、植被覆盖指数、水网密度指数、土地退化指数、污染负荷指数等5个指标，计权确定该市生态环境质量指数为48．7，评价等级为一般；同时选择了资源安全评价、环境安全评价、生物安全评价和灾害安全评价等4个要素，确定该市生态系统安全指数为0．44。     

花垣河软体动物多样性调查和水质评价

对湘西花垣河软体动物的种类以及多样性进行了调查,并用生物多样性指数对花垣河水质进行了评价.8个断面除S1、S3、S8断面的软体动物丰富度指数(DMA)与Shannon-Wiener多样性指数(H')分别介于0.2643～2.4937和0.6765-2.4123外,S2、S4、S5、S7、S8五个断面的软体动物丰富度和多样性指数均为零.研究结果表明,花垣河软体动物资源贫乏,其多样性指数表明,花垣河水体受到严重污染.     

湘江大源渡枢纽底泥中镉、铅的污染特征及其潜在生态风险评价

为研究湘江大源渡枢纽底泥中Cd、Pb的污染特征及其生态风险,采集6个断面的18个底泥样品,测定了沉积物中Cd、Pb的总量、化学形态及其生物有效性,并利用地积累指数法和单因子指数法评价其污染程度与等级.结果表明,湘江大源渡枢纽底泥中Cd、Pb存在很强的积累现象,尤其是Cd污染特别严重.各采样点底泥中Cd主要以碳酸盐结合态...     

2008—2013年全国地表水高锰酸盐指数污染特征分析

为分析近年来中国地表水高锰酸盐指数污染的时空变化规律,利用2008—2013年全国地表水338个可比国控断面监测数据,从时间变化特征、空间分布特征、污染较轻和较重断面变化情况及污染变化原因等方面进行了研究。结果表明:1从年际变化看,全国地表水高锰酸盐指数污染总体呈减轻趋势,平均浓度下降32.2%,劣Ⅴ类断面比例下降5.0个百分点;2从流域分布看,辽河、黄河和海河流域高锰酸盐指数污染程度明显减轻,其他流域较为稳定,海河流域高锰酸盐指数污染一直较重,黄河、松花江、淮河和辽河流域次之,其他流域污染较轻;3污染严重断面由22个降至5个,污染较轻断面稳定在242~248个;4COD排放量的减少在一定程度上促进了地表水高锰酸盐指数污染的减轻,但个别流域水资源严重短缺、纳污量仍较高是流域污染较重的重要原因,污染严重断面主要分布在海河流域,这与其COD接纳量较高、水资源总量较少有直接关系。     

珠江口黄茅海表层海水和沉积物中重金属的分布及评价

根据2014年4月对珠江口黄茅海海域表层海水和沉积物中重金属分布的调查监测,采用单因子指数法、内梅罗指数法和生态危害指数法对其重金属污染水平进行评价。结果显示:该海域表层海水中部分站位的Pb、Cu、Zn和Hg超出第一类海水水质标准,内梅罗指数评价表明其整体处于轻污染水平。表层沉积物中部分站位的Hg、As和Cu超出第一类海洋沉积物质量标准,内梅罗指数评价表明其整体处于重污染水平,生态危害指数评价表明其整体可能面临中度风险,Hg为主要风险因子。表层海水中Pb、Cu、Zn具有同源性,表层沉积物中Pb、As、Zn和Cu具有同源性。     

海南红沙港海水中细菌污染调查与评价

于2006年4-6月在红沙港海域进行了四个航次调查,对海域中5个站位的海水样品进行了细菌学检测.结果表明,四个航次海水粪大肠杆菌群超标率最高为40%,异养细菌总数超标率均达60%以上.四个航次海水粪大肠杆菌单项污染指数平均值分别为0.755、1.792、2.215和0.578,异养细菌总数单项污染指数平均值分别为1.54、2.73、24.04和6.11.生物统计学分析显示,粪大肠杆菌群与异养细菌总数存在一定的正相关关系,其相关系数r2=0.439 9.红沙港海水已受到粪大肠杆菌和异氧细菌污染.     

阳澄湖沉积物中氮、磷及有机质空间分布特征与污染评价

于2020年2月采集了阳澄湖63个监测点位的沉积物样品,测定了沉积物中总磷(TP)、总氮(TN)和有机质(OM)的质量比,分析了其在阳澄湖6个湖区(东湖南、东湖北、中湖南、中湖北、西湖南及西湖北)的空间分布特征,并基于综合污染指数(FF)和有机污染指数(OI)进行了评价。结果表明,沉积物中ω(TN)、ω(TP)和ω(OM)均值分别为1 102,822 mg/kg和32.8 g/kg,其中ω(TN)、ω(OM)在空间分布上存在较高差异性,ω(TP)空间分布总体表现为从西湖向中湖、东湖逐渐降低的趋势,ω(TN)、ω(OM)则与ω(TP)相反;全湖TN污染指数、TP污染指数、FF指数和OI指数评价结果分别为2级(轻度污染)、4级(重度污染)、3级(中度污染)和Ⅲ级(尚清洁)。     

江苏省太湖流域大型底栖无脊椎动物完整性业务化评价指数构建

为支撑流域水生态目标的业务化管理,提高水生态监测和评价的可操作性,突破物种分类鉴定的技术瓶颈,以大型底栖无脊椎动物为研究对象,在江苏省太湖流域布设120个采样点,于2013年1—3月、7—8月和10—11月开展3次监测。以最小干扰为参照状态,对涉及物种丰度、物种多度组成、耐污能力和摄食类群的72个候选指数进行分布范围、判别能力及相关性分析,结合指数获取的便利性及物种分类的难易程度,最终筛选出3个核心指数构成大型底栖无脊椎动物完整性业务化评价指数,其中湖荡、河流和水库的指数为软体动物分类单元数、优势分类单元相对多度和BMWP指数,溪流的指数为ETO分类单元数、前三位优势分类单元相对多度和BMWP指数。经验证,业务化指数与环境梯度有较好的响应关系,且可操作性强,具备开展业务化应用的前景。但目前的流域水生态目标管理尚处于摸索阶段,技术体系还须在业务化过程中不断修正和完善。     

基于底栖动物完整性指数的长江口-杭州湾潮间带水生态状况评价

利用生物完整性指数评价流域水生态状况,所得结果对水环境管理决策有重要指导意义。以2006年崇明东滩底栖动物监测数据为参照状态数据,利用长江口1991—2019年和杭州湾2004—2019年潮间带底栖动物监测数据构建底栖动物完整性指数(B-IBI),最终从56个候选指标中确定了6个核心指标:Marglef指数、软体动物相对多度、甲壳动物+多毛纲相对多度、ASPT、科级生物指数和捕食者相对多度。B-IBI评价结果显示:优秀等级样本有44个,良好等级72个,中等等级31个,较差等级7个,很差等级4个;杭州湾北岸水生态状况显著优于长江口南岸(P<0.05)。经验证,B-IBI与水质综合污染指数呈极显著相关(P<0.01),能够有效指示研究区域的水生态状况。     

连云港主要河流大型底栖无脊椎动物水质生物评价

于2008年5月采用D形网半定量采样法调查了连云港市5条河流7个点位的大型底栖无脊椎动物群落多样性,共获得67个大型底栖无脊椎动物分类单元;其中,昆虫纲双翅目18属、蜻蜓目11属;软体动物24种;环节动物4科4属5种。应用典范对应分析(CCA)排序结果将7个样点分成高TN低DO、高电导率和低TN以及高DO和低电导率3组。Shannon-W iener多样性指数、生物指数和COD水质评价结果表明,多样性指数与生物指数和COD评价结果有较大差异,生物指数和COD评价结果较相似。综合评价结果为青口河的水质属于清洁;蔷薇河、淮沭新河、鲁兰河和新沭河属于轻污至中污。生物指数与TN极显著正相关(r=0.913,p=0.004),多样性指数与TN无相关性(r=0.257,p=0.578)。     

云南个旧土壤农作物重金属污染特征及潜在风险

在实地调查和实验室分析的基础上,对云南省个旧市大屯镇土壤农作物重金属污染状况进行了评价。结果显示:个旧市大屯镇调查区域土壤中Pb、Zn、Cd、As平均质量分数分别为943. 5、454. 8、3. 4、302. 1 mg/kg,分别为国家农用地土壤污染风险管控标准筛选值的7. 8、1. 8、11. 2、10. 1倍,土壤污染严重。土壤Cd的生态危害最强,As、Pb的生态危害次之,Zn表现为轻微的生态危害。从潜在生态危险指数来看,所采集的土壤样品皆表现为极强的生态危害。所采集农作物与食品安全国家标准对比,结果显示,大米中Pb、Cd和As的超标率分别为35%、55%和100%;玉米中Pb、Cd和As的超标率分别为13%、0%和0%;小苦菜Pb、Cd和As的超标率分别为100%、60%、100%;小米菜中Pb、Cd和As的超标率均为100%,蔬菜类的重金属超标情况相对于谷物类较为严重。研究区域土壤样品总量Pb、Zn与有效态皆呈极显著正相关关系,总量Cd与有效态呈弱正相关关系,总量As与有效态表现为相关性不显著。     

铅冶炼区土壤重金属总量和有效态含量的函数分析

采集铅冶炼企业周边3 000 m范围内220个表层土壤样品,测定了有毒有害元素铅、镉、砷和汞的总量和有效态含量,探讨了它们之间的关系。结果表明:研究区土壤受到汞、砷、铅、镉的污染依次明显严重,土壤重金属的总量和有效态含量的变异系数均大于100%,土壤镉、铅、汞、砷的生物有效性系数平均值分别为25.9%、17.2%、0.58%、0.11%。土壤铅、镉和砷的总量与其有效态含量呈显著正相关(P0.001),而汞的总量与其有效态含量的相关性不显著(P0.05)。土壤铅和镉的总量和有效态含量可以用直线函数和幂函数表达,函数反推的有效态值和对应统计值的变异系数不大于10%。     

乌鲁木齐市"菜篮子"基地土壤环境质量现状调查

通过对乌鲁木齐市“菜篮子”种植基地——安宁渠土壤中重金属、农药、多环芳烃等污染物的监测结果分析得出,该区域内的土壤中总砷、总汞、总铬、总镉等重金属和土壤中六六六、滴滴涕等含量均低于国家标准限值,土壤污染综合指数属于安全级别之内,但与历史背景值相比,部分重金属含量呈现明显的增加趋势,尤其是总铅、总砷和总镉的含量增幅较大。污染增加趋势与城市工业发展和交通污染及施用化肥、农药有关。     

Lead and cadmium contaminations in feathers of heron and egret chicks

In birds, concentrations of heavy metal contaminants were associated with their diet and environmental quality. This study presents concentrations of lead and cadmium in feathers and the relationship between concentrations in the feather and stomach content of three species of heron and egret chicks. Cadmium concentrations were higher in the Little Egret (geomean 0.75 μg/g dry weight) and Black-crowned Night Heron (geomean 0.88 μg/g dry weight) chicks than in Grey Heron chicks (geomean 0.48 μg/g dry weight). Lead and cadmium concentrations had significant correlations between feathers and stomach contents of heron and egret chicks. The mean lead and cadmium concentrations in feathers were within the background levels for wild birds. Heron and egret species forage around breeding colony (4–7 km). Lead and cadmium concentrations in heron and egret chicks were moderately associated with those of prey concentrations. These results suggest that contaminant concentrations such as lead and cadmium in feathers of heron and egret chicks can reflect local heavy metal contaminations and serve as a great biological indicator for monitoring heavy metal contamination. In addition, the feathers can be a routine monitoring tool over time and space without harming the wild birds.     

Effects of Flooding on Lead and Cadmium Speciation in Sediments from a Drinking Water Reservoir

Římov water reservoir on the river Malše is the main source of drinking water for the town of České Budějovice and for the majority of inhabitants in the South Bohemian region, Czech Republic. Changes in cadmium and lead contents in bottom sediments before and after an extensive flood on the river Malše in August, 2002 were therefore determined. A five-step sequential extraction procedure was used in order to obtain more detailed information about the influence of the flood on heavy metal retention. In order to determine the mobility of lead and cadmium, the mobility factor (MF) for these heavy metals was calculated. The mobility factor of cadmium showed a significant decrease in the upper parts of the sediment profiles after the flood (e.g., from 59.4% to 49.1%) caused by a release of cadmium especially from the exchangeable fraction. There were no significant changes in the lead mobility factor after the flood, but a decrease of lead concentration in the exchangeable fraction was observed. Presented results show that the flood led to a leaching of the heavy metals present in bottom sediments into the environment.     

辽宁绥中海域海水和表层沉积物中重金属污染评价

根据2009年10月的调查数据对辽宁绥中海域海水和表层沉积物中的重金属(砷、汞、铜、铅、锌和镉)进行了研究。用单因子指数评价法对海水中的重金属进行了评价,结果表明,海水中的Zn、Hg含量均超过《海水水质标准》(GB3097-1997)中Ⅰ类海水水质标准。采用《海洋沉积物质量》(GB 18668-2002)Ⅰ类海洋沉积物质量标准评价,表层沉积物中的As超标一倍以上。采用瑞典科学家Hkanson的潜在生态危害指数法进行评价,生态危害程度As>Hg>Cd>Cu>Zn>Pb。     

Assessment of Metal Contamination in Doñana National Park (Spain) using Crayfish (Procamburus Clarkii)

Water quality assessment in the Aznalcollar area was attempted using multivariate methods based on heavy metal concentrations in red swamp crayfish (Procamburus clarkii). Trace levels of four heavy metals, copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb), were detected in crayfish from eleven different stations. Principal component analysis (PCA) highlighted a gradient of contamination between the sampling stations. Cluster analysis (CA) distinguished three groups of stations. Discriminant analysis also differentiated three groups. The group centroids of the first discriminant function were used to devise an index that varies according to the source of the crayfish. These standardized values are proposed for use as a water quality index. The ability of this index to successfully predict environmental quality was proved with random samples.     

Heavy metal bioaccumulation and metallothionein content in tissues of the sea bream Sparus aurata from three different fish farming systems

The distribution and potential bioaccumulation of dietary and waterborne cadmium and lead in tissues of sea bream (Sparus aurata), a major aquaculture species, was studied in relation to three different fish farming systems. Metallothionein levels in fish tissues were also evaluated. Results demonstrate that metal concentrations in various tissues significantly vary among fish culture systems. Different tissues show different capacity for accumulating heavy metals. The content of both cadmium and lead is not strictly correlated with that of metallothionein. Indeed, the marked accumulation of both metals in liver, as well as the high lead content found in gills and kidney, are not accompanied by a concomitant accumulation of metallothioneins in these tissues. No correlation is present between heavy metals and metallothionein content in muscle tissue. The results also demonstrate that cadmium accumulates mainly via dietary food, whereas lead accumulation is not of food origin. Noteworthy is that the concentration of the two metals found in muscle in all instances is lower than the limits established by European Union legislation for fish destined for human consumption.     

MetalSafe便携式分析仪快速测定水中重金属

以镉和铅为例,采用MetalSafe便携式分析仪快速测定水中重金属,介绍了基于阳极溶出伏安法的测定原理及仪器操作步骤和技术参数.采用标准加入法,镉和铅的校准曲线线性良好,检出限分别为0.022μg/L和0.025μg/L,两个质量浓度水平的镉和铅标准溶液平行测定的RSD≤0.6%,相对误差＜5%.与火焰原子吸收光谱法作...     

Trace metals content in soils along the state road 51 (northeastern Poland)

The aim of the study was to determine concentrations of some trace elements (lead, cadmium, chromium, and nickel) in soils along State Road 51 leading from Olsztyn to Olsztynek, northeastern Poland. The traffic flow had a significant effect on the content of heavy metals in soils lying along the road. Further away from the road, and under a lower traffic flow intensity, the amounts of contaminants originating from the motor traffic decreased. There was a pine forest growing by the road near Olsztyn, which served as a buffer zone for all the analyzed heavy metals. At all the sampling locations, the content of chromium was approximately the same as its natural concentration. The statistical analysis demonstrated that there was a strong negative correlation between the concentrations of nickel, lead, chromium, and cadmium in soils and the distance from the road. The biggest differences in the content of an individual element were determined for lead and the smallest ones—for cadmium. Emissions of trace elements depended on the differences in the traffic flow intensity, number, type, and speed of vehicles and on the atmospheric conditions as well as the distribution of buildings.