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1.
拦河筑坝所导致的物理阻隔和生态阻隔是影响鱼类迁徙的关键因素。圆口铜鱼Coreius guichenoti(SauvageDabry de Thiersant,1874)作为长江上游重要的河流性洄游鱼类,其迁徙不可避免受到金沙江下游向家坝和溪洛渡大型水电站蓄水的影响。关于向家坝和溪洛渡蓄水是否会显著阻隔圆口铜鱼个体的下行以及不同年龄个体之间受阻隔的影响是否存在差异,迄今为止,还未有相关报道。本文拟通过2012—2014年对长江上游永善江段和宜宾江段圆口铜鱼年龄结构变动的研究,探讨向家坝和溪洛渡蓄水对圆口铜鱼不同年龄个体下行阻隔的影响程度。结果表明:1)向家坝和溪洛渡蓄水对圆口铜鱼下行产生了明显的阻隔效应;2)向家坝和溪洛渡蓄水对1龄个体的下行阻隔最明显且最严重;3)与单一的大型水库和大坝相比,多个梯级的大型水库和大坝会对圆口铜鱼的下行产生更为严重的阻隔效应。本文拟为金沙江下游圆口铜鱼的资源保护提供基础数据支持。  相似文献   

2.
对内蒙古西部公路绿化植物油松(Pinus tabulaeformis)、小叶杨(Populus simonii)及其根际土壤中重金属元素(Cd、Hg、Pb、Cu、Zn、Ni、Cr)和类金属元素(As和Se)含量以及根际土壤重金属(Cu、Zn、Pb、Ni和Cr)形态、土壤pH值进行了测定。对比分析了公路沿线不同绿化植物及其不同器官对重金属元素的吸收与积累特征。结果表明:绿化植物根际土壤对重金属元素的吸附及污染程度以Cd为最高。随原子序数的递增,小叶杨和油松两种植物的根部和茎叶两种营养器官中重金属的含量均表现出“N”字形变动趋势。而且重金属元素在不同植物不同器官中的含量具有Zn〉Cu〉Ni,Cr,As,Pb〉Cd〉Hg的基本规律。小叶杨茎叶对重金属元素Cr、Ni和Pb的富集能力较根部为强,油松茎叶对重金属元素Cr、Ni、Cu和Pb的富集能力较根部为强。绿化植物根际土壤重金属元素有效态占总量百分比的大小序列为Zn〉Pb〉Ni、Cr〉Cu,与重金属元素在不同植物不同器官中的含量大小序列Zn〉Cu〉Ni、Cr、As、Pb〉Cd〉Hg并非趋于一致。公路绿化植物对根际土壤中重金属元素的吸收和积累与重金属元素有效态所占的比例有关。  相似文献   

3.
武汉市蔬菜重金属污染现状的调查与评价   总被引:3,自引:0,他引:3  
通过对武汉市6种蔬菜的供食部位及所对应的土壤中重金属Hg(汞)、Cu(铜)、Pb(铅)、Cd(镉)、Cr(铬)、Zn(锌)、As(砷)含量及分布特征进行了检测,结果表明:Pb、Cr是武汉市蔬菜中主要的污染元素;Hg、Cd只在个别叶菜类上超标;Zn、Cu、As无超标样。在所时应的土样中,普遍存在污染的是Cd,其它6种重金属元素均未超标。  相似文献   

4.
于2016年7至10月采用电感耦合等离子体发射光谱法(ICP-OES),测定了内蒙古包头南海子湿地繁殖期过后的白琵鹭(Platalea leucorodia)、苍鹭(Ardea cinerea)和夜鹭(Nycticorax nycticorax)3种鹭鸟初级飞羽及环境因子(水、土壤、食物)中As、Cd、Cr、Cu、Ni、Pb、Zn、Fe、Mn、Hg 10种重金属的含量,采用单因素方差分析方法比较了不同鹭鸟种类羽毛重金属含量差异,并通过生物富集系数及Pearson相关性检验分析了羽毛与环境因子间重金属含量之间的关系,以揭示包头南海子湿地环境中重金属污染现状及生物富集特征。结果表明:(1)被检测的10种重金属中,As、Cd、Cr、Cu、Pb、Zn、Hg 7种元素在湿地环境中均已超标,尤其土壤中Fe、Zn、Cu已达到重度污染的程度。(2)不同重金属元素在鹭鸟羽毛中的含量存在差异,其中Fe元素在白琵鹭羽毛中的含量水平最高(388.77 mg/kg),Cd元素在夜鹭羽毛中的含量最低(0.12 mg/kg)。在鹭鸟羽毛中重金属含量由高至低的顺序分别为,白琵鹭Fe、Zn、Mn、Cu、Hg、Cr、Ni、Pb、As、Cd,苍鹭Zn、Fe、Cu、Cr、Ni、As、Mn、Hg、Pb、Cd,夜鹭Zn、Fe、Mn、Cu、Ni、Pb、Hg、Cr、As、Cd。除Pb和Cd元素外,其他8种元素含量在3种鹭鸟羽毛中的含量种间差异显著。(3)相关分析表明,鹭鸟羽毛中的重金属含量与环境因子中的重金属含量显著相关且呈现富集特征,为此可作为监测当地环境污染的指示性材料。  相似文献   

5.
海口城市土壤重金属污染特征与生态风险评估   总被引:5,自引:0,他引:5  
对海口城市土壤重金属含量、空间分布特征与赋存形态进行了研究,并评估了其生态风险。结果表明,海口城市土壤重金属Hg、As、Cd、Cu、Cr、Ni、Pb、Zn的平均含量分别为0.073、3.82、0.25、26.7、92.4、52.5、29.1和84.1 mg·kg-1。与海口土壤背景值相比,海口城市土壤明显富集重金属Hg、As、Cd、Cu、Cr、Ni、Pb和Zn,受到一定程度重金属污染。Cr、Ni、Cu、Cd和Zn元素主要在郊区富集,Pb主要在路边绿化带中富集,Hg主要在生活区富集。海口城市土壤中Zn、As、Cr、Cu和Ni以残渣态为主,Hg主要以强有机态和残渣态存在,Pb主要以铁锰氧化态和残渣态存在,而Cd则主要以生物可利用态为主。生态风险评价结果显示,海口城市土壤重金属综合生态风险属于微弱水平,但Cd和Hg污染应引起重视。  相似文献   

6.
贵州红枫水库沉积物重金属污染评价及来源分析   总被引:1,自引:0,他引:1  
为了解红枫水库沉积物重金属污染现状,沿库区采集8个点共计80个沉积物样品,采用原子荧光光谱仪及原子吸收光谱仪对重金属Hg、As、Pb、Cd、Cr、Cu、Zn和Ni含量进行了测定,利用地积累指数(Igeo)和潜在生态风险指数(RI)进行污染评价,同时进行相关性分析并讨论其污染来源。结果表明:红枫水库北湖沉积物重金属含量明显高于南湖,8种重金属Hg、As、Pb、Cd、Cr、Cu、Zn、Ni的平均含量依次为0.56、35.76、43.66、0.50、91.03、89.14、152.44和109.30 mg·kg-1;以贵州省土壤背景值为参比,地积累指数评价结果显示Hg为中等污染,污染顺序为HgNiCuAsZnPbCrCd,综合潜在生态风险指数评价结果显示红枫水库为中等生态风险;库区沉积物重金属污染来源于三方面:一是工业排放,主要集中在北湖和中湖,重金属包括Pb、Zn、Cd;二是城市排放及周边农药、化肥残留,主要污染区为北湖、中湖,污染物为Cr、Ni、As和Cu;三是矿区开采,污染覆盖全湖区,主要包括Hg和As。  相似文献   

7.
某农药工业园区周边土壤重金属含量与风险评价   总被引:11,自引:0,他引:11  
Shi NN  Ding YF  Zhao XF  Wang QS 《应用生态学报》2010,21(7):1835-1843
以苏南某农药工业园区周边30km2区域为研究区,采用同心圆法采集土壤样品183个,分析了农药工业园区周边土壤Cd、Cr、Cu、Ni、Pb、Zn、Hg和As8种重金属含量、空间变异性、来源及潜在风险.结果表明:以自然背景值为评价标准,研究区表层土壤Hg、Cu、Cd和Pb平均含量超过自然背景值,其中Hg和Cu含量最高;以国标二级标准为评价标准,土壤Cd、Cr、Ni、Pb、Zn、As6种重金属的单项污染指数平均值均小于1,Hg和Cu分别为1.59和1.05.在农药工业园区周边土壤重金属污染较重的东南方向和西北方向,随着与园区距离的增加,土壤Cd、Ni、Pb、Cr、As、Hg、Zn和Cu含量先上升、后下降、再趋于平稳.通过分析农药工业园区周边土壤重金属综合污染指数发现,距离园区约200~1000m周边土壤污染的风险较大,而1000m以外逐渐达到安全范围.利用地统计学和GIS相结合进行分析发现,8种重金属污染指数有明显的空间变异.依据相关分析与主成分分析结果推测,Zn、Ni、Cr、Pb和As主要来源于成土母质,而Hg、Cu和Cd主要与人类活动有关.  相似文献   

8.
郑曙明 《四川动物》1991,10(3):31-32
有关鱼类细胞核DNA含量的研究,国外有较多的报道,国内自八十年代初陆续开展了这方面的工作,并通过测量DNA含量来探讨鱼类种群关系〔2〕、倍性关系〔1〕和杂交育种等。现采用血涂片,Feulgen染色,显微吸收光度法对长江中的铜鱼Coreius heterodon和圆口铜鱼Coreius guichenoti的红细胞核DNA含量进行了初步测定。1材料与方法材料于1989年5月取自长江上游的四川省泸州市,每种鱼各取5尾。1.1制片用肝素作抗凝剂,用注射器从鱼尾静脉取血,涂布于洁净载玻片的一端,用公鸡血细胞作对照标准,即从公鸡腋静脉取血,涂布于该载玻片上的另一端。涂片空…  相似文献   

9.
江苏省典型区农田土壤及小麦中重金属含量与评价   总被引:20,自引:0,他引:20  
为了研究江苏省典型区地震带农田土壤和小麦中重金属的污染,在具有代表性的农田采集收获期小麦及耕层土壤,分析和评价了土壤和小麦中重金属Cu、Pb、Cd、Ni、Cr、Hg、As和Zn的含量及污染程度。结果表明,土壤样品中Cd、Zn、Pb的含量均超过江苏省土壤背景值,Cr、Cu、Ni和As分别有25.64%、97.44%、92.31%和92.31%的土壤样品中超过江苏省土壤背景值,Hg的含量均在背景值以下;与国家土壤环境质量标准(GB15618—1995)中Ⅱ级标准相比,Cd的含量均超出标准限值,其它7种重金属元素含量均在标准限值以下。土壤中重金属相关分析表明,Cd、Cu、Cr、Ni、Pb、Zn、As具有相同的来源的可能性较大,而Hg与Cd、Cu、Cr、Ni、Pb、Zn、As的来源均不相同。以NY 861—2004为评价标准,小麦籽粒Pb、Cr、Hg、Ni、As样品超标率分别为100%、58.97%、33.33%、10.26%、2.56%,Cu、Zn和Cd没有样品超标,由此可见小麦籽粒中Pb的污染最为严重。采用单因子污染指数法、综合污染指数法和Hakanson潜在生态评价指数法以国家土壤环境质量标准(GB15618—1995)和江苏省土壤背景值为参比值,对农田土壤重金属污染进行评价,结果显示,从单项污染指数来看只有Cd达到重度污染水平,其它元素均在安全范围以内,从综合污染指数来看土壤重金属污染达到中度污染水平,从潜在生态评价指数法来看,研究区域表现为很强的生态危害,并以Cd为主要污染因子。  相似文献   

10.
为探讨油茶(Camellia oleifera)产地土壤和油茶果实中金属元素分布和富集特征,在油茶果实成熟期,对浙江5个油茶产地土壤及油茶果实中金属元素进行污染分析和富集能力评价。结果表明,浙江油茶产地土壤中Pb、Cr、Cd、As、Hg、Ni、Cu和Zn含量低于农用地土壤污染风险筛选值,综合污染等级为安全。个别产区常山县土壤中As、Ni、Cu和江山县土壤中Pb、Cr、Fe含量显著高于其他产地;常山和建德土壤中Cd单因子污染指数分别为0.93和0.81,处于污染警戒线。Cr、Ni、Cu、Zn主要分布在油茶籽中,Hg主要分布在壳中,Pb、Cd、As、Fe和Mn主要分布在青皮中。油茶籽中Cu、Fe、Mn的富集系数大于0.4,吸收能力强,Ni、Zn的富集系数小于0.4,具有一定吸收能力,Pb、Cr、Cd、As和Hg的富集系数小于0.1,吸收能力低;壳中Cu、Mn的富集系数大于0.4,吸收能力强,Fe的富集系数小于0.4,具有一定吸收能力,Pb、Cr、Cd、As、Hg、Ni、Zn的富集系数小于0.1,吸收能力低;青皮中Cu、Fe、Mn的富集系数大于0.4,吸收能力强,Pb、Cr、Cd、As、Hg、Ni、Zn的富集系数小于0.1,吸收能力低。浙江油茶主产区土壤质量安全,适合油茶种植。油茶果实对Cu、Fe、Mn有一定富集能力,对Pb、Cr、Cd、As和Hg无富集能力。  相似文献   

11.
吴城鄱阳湖自然保护区鱼体重金属的富集及安全性评价   总被引:4,自引:0,他引:4  
为研究吴城鄱阳湖自然保护区鱼类重金属的污染情况, 以鄱阳湖吴城6种常见淡水鱼(鲤、鳙、鲢、草鱼、青鱼、鳊)为研究对象, 分别研究鱼心脏、肝脏、鳃丝和肌肉等部位中铜、锌、铅、镉4种重金属的富集情况, 并采用目标危险系数(THQ)评价其健康风险。结果显示, 重金属元素在鱼体不同器官中的富集程度不同, Cd在肝脏中的含量最高, Cu在肝脏和心脏中的含量最高, Pb在肝脏中的富集含量最低, Zn在各器官的总体含量要高于其他3种元素。4种重金属在鱼肌肉中的含量均符合国内外标准。目标危险系数(THQ)分析结果表明, Pb导致的健康风险最高, Cd最低, 单一重金属THQ值和复合重金属TTHQ值均小于1, 说明吴城鄱阳湖自然保护区鱼类重金属的污染程度较低, 不会对消费者健康产生潜在危害。  相似文献   

12.
按离路基不同距离采集土壤、麦苗和籽粒样品, 在测定样品重金属 (Pb、Cd、Zn、Cr和Cu) 的基础上, 开展了路旁土壤-小麦系统重金属分布、积累和污染状况分析, 并对膳食小麦 (Triticumaestivum) 引起的健康风险进行了评价。结果表明:1) 土壤-小麦系统重金属含量随着离开路基距离的增加呈先增加后减少的趋势, 土壤重金属含量>麦苗重金属含量>籽粒重金属含量。2) 麦苗和小麦籽粒对土壤重金属富集能力的大小顺序均为Cu>Cd>Zn>Pb>Cr, 麦苗对重金属的富集能力大于小麦籽粒。3) 膳食小麦所致的Cd个人健康风险较大。  相似文献   

13.
To understand the effect of intense human activities in suburbs on environmental quality, we obtained 758 measurements of the heavy metals in certain farmland soils of the Beijing suburbs. Multivariate statistical analysis and geostatistical analysis were used to conduct a basic analysis of the heavy metal concentrations, the distribution characteristics and the sources of pollution of the farmland soils in these suburbs. The results showed the presence of eight heavy metals in the agricultural soils at levels exceeding the background values for As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn. In particular, all the measured Cr concentrations exceeded the background value, while As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn were present at 1.13, 1.68, 1.95, 1.43, 1.63, 0.79, 0.92 and 1.36 times their background values, respectively. The results of correlation, factor and spatial structure analyses showed that Cd, Cu, Pb and Zn were strongly homologous, whereas Cr and Hg showed a degree of heterogeneity. The analysis further indicated that in addition to natural factors, Cd, Cu, Pb and Zn in the soil were mainly associated with distribution from road traffic and land use status. Different agricultural production measures in the various areas were also important factors that affected the spatial distribution of the soil Cr concentration. The major sources of Hg pollution were landfills for industrial waste and urban domestic garbage, while the spatial distribution of As was more likely to be a result of composite pollution. The regional distribution of the heavy metals indicated that except for Cr and Hg, the high heavy metal levels occurred in districts and counties with higher organic matter concentrations, such as the northwestern and southeastern suburbs of Beijing. There was no significant Ni pollution in the agricultural soils of the Beijing suburbs.  相似文献   

14.
We examined the concentrations of the heavy metals Zn, Cu, Cr, Pb, and Cd in the liver, gonads, and muscles of male and female starry flounderPleuronectes stellatus from Nyiskii Bay (off the northeastern coast of Sakhalin) in August 1996. It is shown that the accumulation of the metals was different in the organs and tissues of males and females. The greatest differences were recorded in the gonads. The concentrations of Zn and Cu were greater in the gonads of females, whereas the concentrations of Cd, Pb, and Cr were greater in male gonads. More Cd and Pb accumulated in the liver of females, whereas the concentrations of Zn and Cd were greater in the muscles of males. The results obtained seem to reflect the specific features of physiological processes in specimens of different sexes and the biochemical composition of the tissues of fish organs during the period of foraging and gonad development. The concentrations of metals in the muscles of starry flounder from Nyiskii Bay did not exceed the sanitary standards.  相似文献   

15.
To investigate the impact of water impoundment on the metal contamination in sediments cores from the three tributaries of Three Gorges Reservoir (TGR), the concentrations, distribution, bioavailability, and potential risk of eight trace metals between summer and winter were analyzed using sequential analysis. The mean contents of all studied metals were higher than the geochemical background value, and were higher in summer than in winter. The results of the partitioning study indicated that Cr and Ni prevailed in the residual fraction, while a small proportion was found in the easily soluble fractions. Cu and Zn were distributed mainly in the residual and reducible fraction, while Cd and Pb were predominantly associated with non-residual fractions. These observations suggested that the most easily mobilized metals in the study area were Cd and Pb. The mean enrichment factors (EF) of Cu, Zn, Cd and Hg were higher than 1.5, revealing the potential anthropogenic inputs, whilst the EF of other metals remained within the range of natural variability. The positive correlation between non-residual Cu, Zn and Cd and their EF values further indicated that anthropogenic inputs were the potentially major contributor for the enrichment of Cu, Zn and Cd in TGR sediments. The results evaluated by both potential ecological risk index and modified risk assessment code (mRAC) of all sampling sites demonstrated the relatively high potential risk of sediment contamination effect in TGR.  相似文献   

16.
于2018年5月—2020年6月对南水北调中线总干渠11个采样点表层水中18种重金属的浓度进行周期性采样监测, 并分别利用USEPA推荐的健康风险评价模型和物种敏感性分布(SSD)法评估常见重金属的人体健康风险水平和水生态风险水平。化学分析结果显示, 18种重金属均被普遍检出, 平均浓度大小排序为: Fe>Sr>Ba>Zn>Ti>Ni>Mn>Cu>V>Cr>As>U>Rb>Se>Pb>Bi>Co>Cd, 均未超出《地表水环境质量标准》(GB 3838—2002)Ⅰ类水标准和《生活饮用水卫生标准》(GB 5749—2006)限值。健康风险评价结果显示, 南水北调中线总干渠表层水中8种常见重金属(Cr、Cd、As、Cu、Pb、Zn、Ni、Mn)对儿童和成人的总健康风险值处于10–8级别。基于构建的8种常见重金属(As、Ni、Pb、Cr、Zn、Se、Cd、Cu)的SSD曲线, 计算重金属对本土淡水生物5%危害浓度(HC5)和潜在影响比例(PAF), 结果显示, 南水北调中线总干渠水中目标重金属对全体水生生物种群的影响比例小于5%, 但Cu和Zn分别可对8.54%和16.77%的藻类种群造成影响, Cr可对6.44%的甲壳类种群造成影响。上述结果表明, 南水北调中线总干渠水中重金属的当前含量不高, 不会对人体造成潜在健康风险; 以保护95%的生物物种为标准, 个别重金属对总干渠中藻类、甲壳类种群可能具有一定潜在风险, 尚有待进一步关注。  相似文献   

17.
Kattedan is an industrial area near Hyderabad, Andhra Pradesh, India, contaminated with high concentrations of metals attributed to industrial sources (battery manufacturing, metal plating, textile and pharmaceuticals production and others). Twelve different locations in the Kattedan industrial area were assessed for concentrations of metals (Zn, Cr, Cu, Ni, Co, Pb, Hg, Cd, and As) in soils, waters, and vegetation. Application of sequential extraction technique for the soils revealed relatively high percentages of Zn, Cu, and Cr associated with mobile fractions, and correspondingly high concentrations of Zn, Cr, Cu, and Pb in forage grass samples and a high degree of bioavailability to humans. Human exposure assessment revealed high concentrations of Pb, Zn, and Cr in blood and urine samples from the residents of the study area showing a direct pathway and a potential for toxicological hazard due to heavy metal pollution.  相似文献   

18.
To identify sources of heavy metal(loid) (HM) contamination in agricultural soils of Huzhou, surface soil samples were sampled from 89 different agricultural regions in 2012. Concentrations of heavy metal(loid)s, along with pH, total phosphorus (TP), total nitrogen (TN), and soil organic matter (SOM), were determined. Ecological risk was then assessed using a modified Hakanson ecological risk index, and the sources of contamination were determined using principal component analysis (PCA). Mean concentrations of heavy metal(loid)s were 10.26, 23.21, 83.75, 22.81, 0.25, 61.86, 33.03, and 0.15 mg kg?1 for As, Cu, Zn, Ni, Cd, Cr, Pb, and Hg, respectively. Cu, Zn, Ni, Cr, Cd, Hg, and Pb were correlated positively with TP and there were obvious positive correlations among Cu, Zn, Ni, Cr, and Cd. Risk index (RI) values varied from 39 to 1246 with a mean value of 137. Enrichment of Pb, Zn, Cu, and especially Cd can be attributed to excessive use of nitrogen and phosphorus fertilizers containing heavy metals, as well to surface irrigation and natural soil formation. While the ecological risk of most agricultural soils in Huzhou is low, it is recommended that the use of phosphate and nitrogen fertilizers be restricted and production technology be improved to reduce the heavy metal(loid) concentrations. Results suggest that the Chinese environmental quality standard for soil should be revised to better address heavy metal(loid) contamination.  相似文献   

19.
A total of 455 agricultural soil samples from four nonferrous mines/smelting sites in Shaoguan City, China, were investigated for concentrations of 10 heavy metals (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, and Zn). The mean concentrations of the metals were 72.4, 5.16, 13.3, 54.8, 84.5, 1.52, 425, 28.2, 529, and 722 mg kg?1, respectively. The values for As, Cd, Hg, Pb, and Zn were more than 8 and 1.5 times higher than their background values in this region and the limit values of Grade II soil quality standard in China, respectively. Estimated ecological risks based on contamination factors and potential ecological risk factors were also high or very high for As, Cd, Hg, and Pb. Multivariate analysis (Pearson's correlation analysis, hierarchical cluster analysis, and principal component analysis) strongly implied three distinct groups; i.e., As/Cu/Hg/Zn, Co/Cr/Mn/Ni, and Cd/Pb. Local anomalies for As, Cu, Hg, and Zn by a probably anthropogenic source (identified as mining activity), Co, Cr, Mn, and Ni by natural contribution, and a mixed source for Cd and Pb, were identified. This is one of the few studies with a focus on potential sources of heavy metals in agricultural topsoil around mining/smelting sites, providing evidence for establishing priorities in the reduction of ecological risks posed by heavy metals in Southern China and elsewhere.  相似文献   

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