适于北江水质生物评价的附着硅藻指数研究

采用主成分、层次聚类、箱型图和双向指示种分析(TWINSPAN)等方法,研究了15项附着硅藻指数在北江流域的适用性。在北江流域25个监测点中,共鉴定出附着硅藻2目6科30属98个种和亚种,相对丰度为5%以上的硅藻属有曲壳藻属(Achnanthes)、菱形藻属(Nitzschia)、舟形藻属(Navicula)和直链藻属(Melosira),分别为34.4%、18.1%、8.6%和7.3%。相对丰度为5%以上的硅藻种有极小曲壳藻(Achnanthes minutissima),极小曲丝藻(Achnanthidium minutissimum),克劳斯菱形藻(Nitzschia clausii)和可变直链藻(Melosira varians)。附着硅藻指数间,罗特营养指数(Rott Trophic Index,ROTT)和洛博指数(Lobo Index,LOBO)与其他指数相关性较弱,硅藻生物指数(Biological Diatom Index,IBD)和富营养污染硅藻指数(Diatom Eutrophication Pollution Index,EPI-D)呈极显著相关(r=0.915,P0.01)。硅藻指数与水质指标的相关性分析表明,斯雷德切克指数(Sláde?ek Index,SLA)和LOBO与电导率(Cond)、溶解氧(DO)和总磷(TP)等10项水质指标间均无相关性,其他指数与某个或某几个水质指标有一定的相关性。对10项水质指标加权后进行层次聚类,结果表明阿图瓦-皮卡第硅藻指数(Artois-Picardy Diatom Index,IDAP)、特定污染敏感指数(Specific Polluosensitivity Index,IPS)、硅藻属指数(Generic Diatom Index,IDG)和IBD与水质分类结果较一致。利用TWINSPAN对样点和硅藻群落进行分类后绘制箱型图,结果表明,IBD对样点水质的变化最为敏感。结果表明,IBD是适合北江流域水质评价的硅藻指数。     

武汉月湖近代沉积物中的硅藻组合与环境关系研究

采集武汉月湖2处近代沉积物,分析了沉积硅藻组合与其环境关系,共发现24属83种硅藻。结果表明：2个柱状沉积物中硅藻优势属为小环藻属、直链藻属、舟形藻属、Cyclostephanos属。Z-1钻孔共有20属61种硅藻,Z-2钻孔共有24属68种硅藻。Z-1钻孔优势种为梅尼小环藻（Cyclotella meneghiniana）、颗粒直链藻（Aulacoseira granulata）、Navicula porifera、Cyclostephanos tholifomis。Z-2钻孔优势种为梅尼小环藻、颗粒直链藻、舟形藻（Navicula sp.）、Cyclostephanos invisitatus。就硅藻密度分布而言,总趋势上层最多,平均7.14×10^5～58.65×10^5 ind.g-1,中层其次,平均0.08×10^5～13.98×10^5 ind.g-1,下层最少,平均0.24×10^5～0.64×10^5 ind.g-1。硅藻种数最少的样品出现在沉积物中层,梅尼小环藻、颗粒直链藻、舟形藻、Navicula porifera、Cyclostephanos tholifomis、Cyclostephanos invisitatus的组合可以指示湖泊水体环境出现富营养化。通过探讨分析影响硅藻分布的环境因素,为恢复月湖近代水环境演化过程提供了依据。     

嘉陵江出口段三类水体蓝绿硅藻优势种变化机理

三峡水库的河流型、过渡型、湖泊型水体中后两者为富营养化敏感水体,为认识富营养化敏感时期嘉陵江出口段三类水体蓝藻(Cyanophyta)、绿藻(Chlorophyta)、硅藻(Bacillariophyta)优势种变化及机理,2007年9月至2008年8月进行了三种藻类的现场调查分析.结果表明,在3～7月份,总藻种数为52种,占全年种数的66.5%,平均密度43.76×104个-L-1,为全年中最高,因此3-7月为富营养化敏感期;优势藻种类变化为河流型蓝、绿、硅藻分别为6、4、9种,过渡型的蓝、绿、硅藻分别为4、5、4种,湖泊型的蓝、绿、硅藻分别为6、5、3种;蓝、绿、硅各优势藻的平均优势度在2.5m·s-1为0.11,2.0 m·s-1为0.11,1.5 m·s-1为0.10,0.05～0.2 m·s-1为0.07,＜0.05 m·s-1为0.06.分析认为,蓝、绿、硅优藻种数变化与流速有关,优势硅藻种数与流速正相关,优势蓝、绿藻数与流速反相关;具有硅壳的硅藻需要借助流速浮动进行光合作用,适宜0.05～2.5 m·s-1水体;大型硅藻可能通过进化中的硅壳薄化来适应一定流速的水体;蓝藻、绿藻沉降系数小,有的具有气囊或鞭毛,因而易浮动进行光合作用,适宜0.2 m·s-1以下的水体;优势蓝、绿、硅藻的平均优势度与优势藻多样性负相关.随着嘉陵江出口段采样点的流速逐渐减小,优势蓝、绿、硅藻的平均优势度逐渐变小,而优势藻多样性逐渐增大.     

东江干流浮游植物群落结构特征及与水质的关系

2009年7月,调查了东江干流浮游植物的属类组成、密度和生物多样性指数,并将水质理化参数与藻类的群落指标进行相关性分析。47个采样点中共发现7门78属藻类,浮游植物的密度范围在0.72×104~853.86×104 cells.L-1之间。其中蓝藻门、硅藻门、绿藻门和隐藻门占总浮游植物密度的96.12%,优势属为颤藻属、隐藻属、小环藻属、菱形藻属、栅藻属。根据藻类各项指标值显示,东江干流水质良好。相关分析结果表明：浮游植物密度以及属类数均与CODMn及电导率呈极显著的正相关关系（P〈0.01）。并且CCA分析表明CODMn浓度是影响这一区域物种分布格局的重要因素。     

安徽省石塘湖过去百余年湖水总磷浓度的定量重建

湖水总磷浓度对湖泊富营养化有很好的预警作用,历史湖水总磷浓度的定量重建能揭示湖泊营养演化历史.依据安徽省石塘湖沉积物钻孔的高分辨率硅藻研究结果,结合长江中下游湖泊硅藻-总磷转换函数模型,定量重建了其过去百余年来硅藻组合演替与历史湖水总磷浓度的变化过程.结果表明:石塘湖硅藻经历了从颗粒直链藻(Aulacoseira granulate)优势组合(1867-1981年)向富营养属种高山直链藻(Aulacoseira alpigae)优势组合(1981年以来)的变化.1981年以前,水体ρ(总磷)为50～60μg.L-1,湖泊一直维持在中等营养水平;1981年之后水体ρ(总磷)呈现明显升高趋势(＞100 μg·L-l),硅藻组合以高山直链藻占绝对优势,同时伴有喜好富营养环境的属种如极微小环藻(Cyclotella atomus)、梅尼小环藻(Cyclotella meneghiniana)、谷皮菱形藻(Nitzschia palea)和汉斯冠盘藻(Stephanodiscus hantzschii)等的增加,标志着湖泊富营养化的发生.20世纪80年代以来,农业及城市生活污水排放、农业化学肥料的大量使用以及过度养殖是硅藻种群转变和富营养化发生的主要根源.增温在一定程度上也影响着硅藻群落变化和富营养化的加重.根据重建的硅藻-水体总磷浓度结果,提出石塘湖治理的营养物基准水体ρ(总磷)为60 μg·L-1,为该湖整治和修复方案的制定提供可参考的目标,也为当地大量类似湖泊的治理提供重要参考.     

漓江桂林市区段夏季浮游植物群落特征与水质评价

浮游植物是水生态系统的重要组成部分,其群落结构变化与水体环境条件密切相关,能直接影响水生态系统的功能,是水环境质量优劣的重要指示因子之一。为揭示漓江流域浮游植物群落结构特征及其与水质的相互关系,2012年8月对漓江桂林市区段干流（桂林赵家桥村至桂林王家村）的理化指标及浮游植物的群落组成分布进行了分析研究,并结合水体理化指标和生物指数对漓江水质进行了评价。结果表明,漓江水体高锰酸盐指数、总氮、总磷、氨氮的变化范围依次为1.80-6.20、1.12-2.68、0.022-0.282、0.34-1.73 mg·L-1,其含量在上游变化平稳,到三条支流汇入处大幅增高,最高值均出现在南溪河入口处。共调查到浮游植物7门60属128种,其中硅藻50种（占种类组成的39.06%）,绿藻52种（占40.63%）,蓝藻16种（占12.50%）,裸藻7种（占5.47%）,黄藻、金藻和甲藻各1种（分别占0.78%）。优势种依次为冠盘藻（S. tephanodiscus）、蛋白核小球藻（C. pyrenoidosa）、喙头舟形藻（N.rhynchocephala）、短小舟形藻（N.exigua）、广缘小环藻（C.Bodanica）、四尾栅藻（S.quadricanda）和肘状针杆藻（S. ulna）。浮游植物密度为10.3×10^4-1047.0×10^4ind.·L^-1,平均密度为474.7×10^4 ind.·L^-1,其中密度最小的是赵家桥村,密度最大的是南溪河入口;种类上绿藻门占据多数,密度和优势种分布上以硅藻居多,总体上属于硅藻-绿藻型水体。浮游植物多样性指数Shannon-Wiener指数（H）在1.60-4.27之间,Simpson指数（D）在2.24-12.74之间,水质总体上为清洁-轻度污染。Margalef指数（d）在1.85-4.23之间,Pielou指数（J）在0.40-0.83之间,指数值总体较高,漓江水体中浮游植物群落结构比较稳定,受外界环境的影响较小。漓江干流水质总体上属于Ⅱ-Ⅲ类水体,在支流汇入处理化指标浓度增加,浮游植物多样性指     

具有短水力滞留的小型富营养化水库浮游植物群落结构与动态

竹仙洞水库是珠海市对澳门直接供水的水库,也是拱北水厂的重要的水源地.于2006年4月到12月,每2月一次调查了竹仙洞水库水文、水质和浮游植物分布,分析了浮游植物群落季节动态特征.浮游植种类不多,5次采样共检到61种.在丰度上,浮游植物主要以衣藻(Chlamydomonas sp.)、小环藻(Cyclotella meneghiniana)、游丝藻(Planktonema sp.)和隐藻(Cryptomonas sp.)等优势种为主,在生物量上以绿藻和硅藻为优势类群.蓝藻在竹仙洞水库的相对优势并不明显.应用典范对应分析(CCA)对竹仙洞水库浮游植物与环境因子关系分析,环境因子中的pH值、水位、正磷和水力滞留时间对浮游植物的分布影响最大;而透明度和降雨量对其也有一定的影响.从种类分布状况看,衣藻、游丝藻、隐藻对水体中环境因子的敏感性明显高于其它种类,这些种类的相对丰度在低温、低水位和较长水力滞留时间的4月份较高;硅藻门的直链藻(Melosira spp.)、菱形藻(Nitzchia sp.)和裸藻门的梭裸藻(Euglena acus)3种细胞体积较大的种类分布主要受降雨量和透明度的影响,在6月、8月和12月具有较高的相对丰度.与其它热带-亚热带富营养型水库相比,竹仙洞水库的浮游植物群落具有种类相对较少、以绿藻丰度较大的特点;直径在20 μm以上的鞭毛绿藻和丝状绿藻以及细胞较小的硅藻门的小环藻是生物量的主要贡献者,短水力滞留时间是浮游植物群落结构与动态变化的关键控制因子.     

深圳湾浮游植物的季节变化

2008年2月至11月对深圳湾的浮游植物和理化环境因子进行了4个季度月的调查,结果共检出浮游植物150种（包括变种和变型）：春季66种、夏季72种、秋季54种、冬季50种,其中硅藻门36属108种,甲藻门14属36种,绿藻门3属3种,蓝藻门2属3种。优势种共有湖沼圆筛藻Coscinodiscus lacustris、中肋骨条藻Skeletonema costatum、夜光藻Noctiluca scientillans 3种：春季1种、夏季1种、秋季1种、冬季2种,优势种群由春夏季的湖沼圆筛藻演替至秋季的中肋骨条藻、冬季的中肋骨条藻和夜光藻,没有全年广布优势种;4季均出现的种类共有9种,其中硅藻8种,甲藻1种,各季节间共有种类数在13～31种,Jaccard种类相似性指数范围在0.12~0.35,季节更替明显。多样性指数和均匀度的变化范围分别为0.006~1.724和0.001~0.306,群落结构较脆弱。细胞密度在1.25×107~217.90×107 cells.m-3,夏季最高,春季次之,冬季最低,属季节单峰型变化,与一般亚热带春、秋季出现密度高峰不一致,这与深圳湾陆源营养物质的扰动有关,其无机氮和活性磷酸盐含量均劣于国家海水水质标准的四类水,因此,该海域水质营养类型属于亚热带富营养型。细胞密度与硅酸盐呈极显著的负相关,相关系数为-0.446（p〈0.01,n=36,双尾）,与水温呈显著的正相关,相关系数为0.371（p〈0.05,n=36,双尾）,与其他因子的相关性不明显。从优势种的种类数和多样性指数分析,深圳湾浮游植物的群落结构已趋于单一化,生态系统抗干扰能力极为脆弱。     

水生植物滤床去除富营养化湖泊水中微囊藻毒素的研究

水生植物滤床(HFB)是一种用于净化富营养化水体的新型无基质型人工湿地系统。为考察HFB系统对水体中微囊藻毒素的处理效果,在太湖湖滨进行了中试研究。结果表明,在7—9月份,总藻毒素去除率在36.5%~75.8%之间,平均去除率为59.4%;胞外藻毒素平均去除率为50.0%;胞内藻毒素平均去除率为63.9%。不同植物组合型式的HFB系统对总藻毒素去除效果无显著差异。在水力负荷1.0~6.0m3/(m2·d)范围内,HFB系统去除藻毒素效果也无显著差异。系统对藻毒素的去除效果与富营养化指标(叶绿素-a、CODMn、TP)的处理效果成直线正相关性,藻毒素可作为一辅助指标从健康效应角度来反映富营养化水体水质改善情况。HFB系统在水源地藻毒素污染控制方面具有应用价值。     

武汉月湖水体营养物质的分布与硅藻的生态指示

通过对武汉月湖2007年1-12月水体理化指标(电导率、溶解氧、pH值、水温、透明度、无机氮、无机磷、可溶硅)、生物指标(硅藻、蓝藻、叶绿素a)的监测,结果表明:月湖水体中无机氮、无机磷含量较丰富,可溶硅含量较低;月湖水体初级生产力较高,湖泊中蓝藻密度远大于硅藻密度;月湖水体中浮游植物与生境因素有着复杂的生态网络关系.月湖水体营养盐结构不合理,在硅藻消亡后,湖泊水域中的营养组合(丰富的氮与磷,但缺乏可溶硅),这种特殊生境刺激蓝藻的生长,进一步导致硅藻的减少,使月湖浮游植物的优势种转变成蓝藻类.可溶硅在湖泊浮游植物群落由硅藻型向蓝藻演变的过程中起着重要的作用,可溶硅起始浓度水平不仅决定硅藻生产量最大值的程度,而且制约着硅藻持续时间,补偿湖泊可溶硅可能是防治湖泊富营养化的新路.     

Cadmium,copper, and zinc in carrots in Japan

Cadmium (Cd), copper (Cu), and zinc (Zn) in carrots obtained from different regions throughout Japan were assessed in a baseline study on the contents of trace metals in foods. These three metals were measured by flameless atomic absorption spectrophotometry. The geometric mean contents (with one geometric standard deviation indicated in parentheses) of Cd, Cu, and Zn were 0.02 (2.2), 0.7 (2.1), and 2.4 (1.6) mg?kg^?1 wet weight in carrots obtained in Japan. While there was a close relationship among the contents of the three metals in the carrots grown in Cambisols and Gleysols, a significant relationship was recognized only between the contents of Cd and Zn in those grown in Andosols and Fluvic Gleysols. Cd and Zn are classified as 2B metals in the periodic table of elements, and the authors speculate that the similarity of the metal characteristics between Cd and Zn may be responsible for the close relationship in the contents of the two metals, with no relation to the soil type.     

Residues of PCDD,PCDF, and PCBs in some marine organisms in Lake Temsah,Ismailia, Egypt

Residues of PCDDs/F, non-ortho, mono-ortho PCBs, and other PCBs were monitored in the tissues of mullet fish, bolti fish, bivalves and crab taken from Lake Temsah, at Ismailia, Egypt.

Results showed that 2,3,7,8 Tetra CDD and 1,2,3,7,8 Penta CDD were the most frequently detected PCDD congeners. Similarly, 2,3,7,8 Tetra CDF, 1,2,3,7,8 Penta CDF and 2,3,4,7,8 Penta CDF were the most frequently detected PCDF congeners. No relationship was apparent between the concentrations of detected PCDDs congeners and the degree of chlorination, except with crab samples in which an increase in the chlorination coincided with a decrease in the concentrations of the congeners.

In PCDF congeners, detected residues have had a reversed relationship with chlorination increase. In PCDD congeners, Octa CDD had the highest detected concentrations in the two fish species, while in the bivalves and crab, 2,3,7,8 Tetra CDD had the highest concentrations. The mullet fish had the highest total PCDDs concentration, at 0.398?pg/g fresh weight, followed by crab at 0.395?pg/g fresh weight, then bivalves and bolti fish at 0.187 and 0.062?pg/g fresh weight, respectively. In all the examined organisms, the total concentrations of PCDFs were much higher than the total concentrations of the PCDD congeners. The WHO–TEQ values were 11.92, 39.12, 25, and 3.6?pg/g fresh weight, for mullet fish, bolti fish, bivlaves and crab, respectively. The concentration of the mono-ortho congeners CB 118 was the highest detected of all non-ortho and mono-ortho PCBs congeners, with values of 0.382, 0.022, 0.231 and 0.357?ng/g fresh weight, in mullet fish, bolti fish, bivalves and crab, respectively. The WHO–TEQ concentrations were 0.799, 0.003?pg/g fw, 0.05?pg/g fresh weight, 0.676?pg/g, and 0.799?pg/g fresh weight, for the same species, respectively. The total concentration of PCBs 28, 52, 95, 99, 101, 105, 110, 118, 138, 146, 149, 151, 153, 170, 177, 180, 187 were 6.86?ng/g fresh weight for mullet fish, 0.2?ng/g fresh weight, for bolti fish, 2.72?ng/g fresh weight for bivalves and 2.8?ng/g fresh weight for crab, respectively.     

Applications of chitosan in food,pharmaceuticals, medicine,cosmetics, agriculture,textiles, pulp and paper,biotechnology, and environmental chemistry

Environmental Chemistry Letters - Chitosan is a biopolymer obtained from chitin, one of the most abundant and renewable materials on Earth. Chitin is a primary component of cell walls in fungi, the...     

Metal Concentration in Oyster, Crassostrea Gigas, and Sediment in Ann-Ping Mariculture Ground, Taiwan

This study was to assess the metal contamination in oyster tissue grown in the Ann-ping mariculture ground in Taiwan. the information generated from this work also revealed general metal pollution problem for Taiwan's oyster farmers. Oysters, Crassostrea gigas, and surficial sediments collected from ten locations in Ann-ping mariculture ground in Taiwan for metals concentration (Cu, Zn, Pd, Cd, Fe and Mn) were performed. Analytical results indicated that the yearly averaged oyster copper concentrations (μg g^-1, wet weight) in oyster soft parts from Ann-ping increased from 21.3±4.1 in 1993; 24.1±6.8 in 1994; 36.8±11.9 in 1995 to 43.9±23.1 μg g^-1, wet weight, in the 1996 raising season. the mean oyster copper concentration reached a level of 50 μg g^-1, wet weight, in December 1996. This increasing trend of metal concentration in oyster tissue indicates a potential pollution source which may pose a potential disaster as green oyster incidence, which occurred on the Charting coast in 1986, in Taiwan. Sediment samples in Ann-ping mariculture ground were also collected and examined. the seasonal variation of the copper concentration in surficial sediment from Ann-ping did not show an increasing trend as observed in oyster tissue.     

Platinum pollution in road dusts,roadside soils,and tree barks in Seoul,Korea

This study presents the level of platinum in urban environment in and around Seoul, the capital city of Korea. Road dust, roadside soil, and tree bark samples were collected from the sites of various traffic volumes and from control sites in the suburbs. The above samples were analyzed for Pt by ICP-MS and other heavy metals by ICP-OES. Platinum levels in road dusts and roadside soils from Seoul were in the range of 3.8–444 ng/g (av. 115.0 ng/g) and 0.7–221 ng/g (av. 49.7 ng/g), respectively, whereas those in the suburbs were in the range of 2.3–5.2 ng/g (av. 3.9 ng/g) in road dusts and 0.4–5.1 ng/g (av. 2.4 ng/g) in roadside soils. The highest Pt levels in road dusts were found from major roads with high traffic volume. The remarkable difference in average Pt level between heavy traffic roads (av. 132.2 ng/g) and light traffic roads (av. 22.8 ng/g) reflects that an important source of Pt in roadside environment is automobile catalytic converter. High Pt level in road dust was found from the site of erratic stop–start driving condition, for example, 178 ng/g Pt in road dust around a vehicle crossing gate. Platinum level in tree barks ranged from 0.9 to 4.5 ng/g, which indicates the existence of Pt-containing particulate matter in the atmosphere. Road dusts with high Pt level were enriched in traffic-related heavy metals.     

Platinum pollution in road dusts,roadside soils,and tree barks in Seoul,Korea

This study presents the level of platinum in urban environment in and around Seoul, the capital city of Korea. Road dust, roadside soil, and tree bark samples were collected from the sites of various traffic volumes and from control sites in the suburbs. The above samples were analyzed for Pt by ICP-MS and other heavy metals by ICP-OES. Platinum levels in road dusts and roadside soils from Seoul were in the range of 3.8–444 ng/g (av. 115.0 ng/g) and 0.7–221 ng/g (av. 49.7 ng/g), respectively, whereas those in the suburbs were in the range of 2.3–5.2 ng/g (av. 3.9 ng/g) in road dusts and 0.4–5.1 ng/g (av. 2.4 ng/g) in roadside soils. The highest Pt levels in road dusts were found from major roads with high traffic volume. The remarkable difference in average Pt level between heavy traffic roads (av. 132.2 ng/g) and light traffic roads (av. 22.8 ng/g) reflects that an important source of Pt in roadside environment is automobile catalytic converter. High Pt level in road dust was found from the site of erratic stop–start driving condition, for example, 178 ng/g Pt in road dust around a vehicle crossing gate. Platinum level in tree barks ranged from 0.9 to 4.5 ng/g, which indicates the existence of Pt-containing particulate matter in the atmosphere. Road dusts with high Pt level were enriched in traffic-related heavy metals.

     

Metal concentration changes in growing Pacific oysters,Crassostrea gigas,cultivated in Tasmania,Australia

Pacific oyster spat (Crassostrea gigas Thunberg) transferred from the Tamar Estuary to two growing areas in southern Tasmania were monitored for their metal contents over one growing season (1974–1975). Oysters at Pipeclay Lagoon were grown with stick and tray culture while those at Dart Island were cultured with the longline technique. Metal content of the oysters increased with time and the trend was similar to the weight growth curves. Mean dry weights of oysters increased from 0.07 to 1.19 g at Pipeclay Lagoon and from 0.25 to 1.47 g at Dart Island. Metal contents (g) increased at each site, respectively: Fe 57 to 326; 91 to 446; Zn 259 to 6 555; 755 to 5 335; Cd 1.5 to 13.3; 1.9 to 16.3; Cu 26 to 142; 9 to 116; Pb 1.9 to 11.9; 0.6 to 3.8. Concentration curves generally showed a downward trend with time. The relationships of metal concentrations with weight did not differ from sample to sample at a site nor did they differ at one site compared with the other. The only exception was lead, which showed no relationship of concentration with weight at Pipeclay Lagoon and a negative one at Dart Island. It is postulated that higher winter concentrations of metals in the oysters were linked with greater solubility of metal ions in lower salinity water.     

Metal Concentration in Oyster,Crassostrea Gigas,and Sediment in Ann-Ping Mariculture Ground,Taiwan

Abstract

This study was to assess the metal contamination in oyster tissue grown in the Ann-ping mariculture ground in Taiwan. the information generated from this work also revealed general metal pollution problem for Taiwan's oyster farmers. Oysters, Crassostrea gigas, and surficial sediments collected from ten locations in Ann-ping mariculture ground in Taiwan for metals concentration (Cu, Zn, Pd, Cd, Fe and Mn) were performed. Analytical results indicated that the yearly averaged oyster copper concentrations (μg g^?1, wet weight) in oyster soft parts from Ann-ping increased from 21.3±4.1 in 1993; 24.1±6.8 in 1994; 36.8±11.9 in 1995 to 43.9±23.1 μg g^?1, wet weight, in the 1996 raising season. the mean oyster copper concentration reached a level of 50 μg g^?1, wet weight, in December 1996. This increasing trend of metal concentration in oyster tissue indicates a potential pollution source which may pose a potential disaster as green oyster incidence, which occurred on the Charting coast in 1986, in Taiwan. Sediment samples in Ann-ping mariculture ground were also collected and examined. the seasonal variation of the copper concentration in surficial sediment from Ann-ping did not show an increasing trend as observed in oyster tissue.