Spatial and temporal distribution of cadmium and copper in water and zooplankton in the Bahía Blanca estuary,Argentina     

Melisa Daiana Fernández Severini  Sandra Elizabeth BottéMónica Susana Hoffmeyer  Jorge Eduardo Marcovecchio 《Estuarine, Coastal and Shelf Science》2009

Cadmium and copper in the dissolved and particulate phase and in zooplankton were determined in the Bahía Blanca estuary during six surveys from March to December 2005. Temperature, pH, salinity, dissolved oxygen, suspended particulate matter, particulate organic matter and chlorophyll-a were also considered. Dissolved Cd was below the detection limit (0.2 μg L⁻¹) for almost the entire study period whereas Cu concentrations (0.5–2.4 μg L⁻¹) indicated a continuous dissolved Cu input. Particulate Cd concentrations ranged from below the detection limit (<0.01) to 28.6 μg g⁻¹ d.w. while particulate Cu ranged from below the detection limit (<0.04) to 53.5 μg g⁻¹ d.w. Cd in mesozooplankton ranged from below the detection limit (<0.01) to 37.4 μg g⁻¹ d.w. Some of the Cd levels were higher than those reported for other aquatic ecosystems. Cu in the mesozooplankton ranged from 1.3 to 89.3 μg g⁻¹ d.w., values which were within the reported values or higher than other studies. The log of the partition coefficients (log (K_d)) of Cd was 0.04, while log (K_d) for Cu ranged from −0.39 to 2.79. These values were lower than both those calculated for other estuaries and the typical coefficients for marine environments. The log of the bioconcentration factor (log BCF) of Cd was 1.78, indicating that Cd concentration was higher in the zooplankton than in the dissolved phase. Log BCF of Cu ranged from 1.15 to 3. The logs of the biomagnification factors (log BMF) of Cd were low, with a range between −3.45 and 2.21 and those for Cu ranged from −0.1 to 3.35. Positive values indicate biomagnification while negative values indicate biodiminution. In general, no significant dissolved Cd concentration appeared to be present in the Bahía Blanca estuary and Cu values did not indicate a critical environmental status. The particulate phase seemed to be the major carrier for Cd and Cu and TPCu values were within the normal values for an anthropogenically stressed estuary but not for a strongly polluted system. This fraction was the most important metal source for the mesozooplankton. Moreover, the highest metal concentrations were in the mesozooplankton since most of the bioconcentration and biomagnification factors were positive, especially for Cu.  相似文献   

Metallothioneins and cytosolic metals in Neomysis integer exposed to cadmium at different salinities     

Erk M  Muyssen BT  Ghekiere A  Janssen CR 《Marine environmental research》2008,65(5):437-444

In the present study the induction of metallothioneins (MTs) and its relation to cytosolic metal concentrations (Zn, Cu and Cd) in the euryhaline crustacean Neomysis integer exposed to Cd at different salinities was studied. N. integer was exposed to the same free cadmium ion activity of 5.74 x 10(-9) mol l(-1) (i.e. 1/5 of the 96 h LC(50) value expressed as cadmium activity) in hypo-osmotic (5 psu), isosmotic (16 psu) and hyper-osmotic media (25 psu) for 7 days. In this way, the effect of salinity on cadmium speciation was eliminated and therefore the physiological effect of salinity on Cd accumulation and MT induction could be studied. The accumulation of cytosolic Cd in N. integer changed with salinity from 1.11+/-0.05 micromol l(-1) at 5 psu up to 1.43+/-0.17 micromol l(-1) at 25 psu. This could indicate that the physiological response of euryhaline estuarine invertebrates like N. integer to salinity changes can influence the rate of trace metal uptake from solution. While the salinity changes did not cause significant differences in cytosolic Zn concentrations (mean value of all tested salinities: 34.4+/-2.8 micromol l(-1)), an inverse relationship between salinity and cytosolic Cu concentration was observed. The highest concentration of 15.7+/-2.3 micromol Cul(-1) was determined at 5 psu and the lowest 10.9+/-1.4 micromol Cul(-1) at 25 psu. This could point to a possible relationship between the copper concentration and the hemocyanin metabolism in N. integer. This is the first time that differential pulse voltammetry method was applied to MT assays with N. integer. Although the exposure to Cd resulted in a higher Cd cytosolic concentration, no subsequent MT increase was detected. The significant positive correlation between MT levels and cytosolic Cu concentrations (Spearman correlation coefficient r(s)=0.356, p=0.009) implies a strong relationship between MT and Cu in N. integer.  相似文献   

BIOCHEMICAL STUDIES ON “SUB-MICROMETER PARTICLES" AT DAYA BAY I. STUDY ON CONCENTRATION, DISTRIBUTION AND CORRELATION OF TRACE METALS IN DIFFERENT SIZE FRACTIONS     

李丽  张正斌  王肇鼎  赵伟  彭云辉  黄洪辉  潘明祥 《中国海洋湖沼学报》2000,18(4)

ＩＮＴＲＯＤＵＣＴＩＯＮＣｏｌｌｏｉｄｓ (ｏｒｓｕｂ ｍｉｃｒｏｍｅｔｅｒｐａｒｔｉｃｌｅｓ)ａｒｅｏｐｅｒａｔｉｏｎａｌｌｙｄｅｆｉｎｅｄａｓｐａｒｔｉｃｌｅｓｂｅｔｗｅｅｎ 1ｎｍａｎｄ1 μｍ (Ｖｏｌｄ ,Ｒ .Ｄ .ａｎｄＶｏｌｄ ,Ｍ .Ｊ.,1 983) .Ｔｈｅｄｉｓｔｒｉｂｕｔｉｏｎｂｅｔｗｅｅｎ“ｄｉｓｓｏｌｖｅｄ”ａｎｄ“ｐａｒｔｉｃｕ ｌａｔｅ”ｐｈａｓｅｉｎａｑｕａｔｉｃｃｈｅｍｉｓｔｒｙｕｓｅｄｔｏｂｅｄｅｆｉｎｅｄｂｙａｆｉｌｔｒａｔｉｏｎｗｉｔｈ 0 .45 μｍｐｏｒｅｓｉｚｅｆｉｌｔｅｒｓ.Ｔｈ…  相似文献   

云南大平掌铜-多金属矿床成矿金属来源初探   总被引：2，自引：1，他引：2       下载免费PDF全文

钟宏  胡瑞忠  叶造军 《地质科学》2001,36(1):72-82

大平掌铜-多金属矿床是我国西南“三江”地区新发现的火山岩型块状硫化物矿床,微量元素、稀土元素及铅同位素地球化学研究表明,成矿金属元素主要来源于对流循环的海底热卤水对火山岩围岩的淋滤作用。成矿过程中细碧岩、角斑岩、石英角斑岩均可能提供较多的Cu、Au,角斑岩、石英角斑岩可能贡献较多的Pb,而角斑岩则可能提供较多的Zn。  相似文献   

过去20年矿床事业发展的概略回顾   总被引：17，自引：4，他引：17  

涂光炽 《矿床地质》2001,20(1):1-9

文章概略回顾了过去20年在找矿和成矿理论研究方面获得的若干重要成就。指出这一阶段虽在一些国家存在矿业不景气，但找矿进展，特别是金、铜矿床、仍很出色。矿业中国都强调了超大型矿床的重要性。在成矿理论方面，主要就多样复杂的海底成矿，三大巨型成矿域，成矿模式，中酸性岩浆岩及有关成矿作用，层控矿床，同位素、微量元素及气液包裹体运用于成矿等问题的研究历史作了回顾。  相似文献   

浅析小秦岭西段驾鹿金矿田构造与金成矿的关系     

高珍权  刘继顺  陈德兴 《大地构造与成矿学》2001,25(4):439-445

本文在研究构造与金成矿的地质关系的基础上，从不同方向断裂充填物的微量元素的分 布特征、地质产状、粒度不同的黄铁矿中金的分布特征、不同期次的断裂充填物的微量元素分布特 征等方面详细探讨了构造与金成矿的地球化学关系。认为不同方向构造充填物的微量元素的分布 特征很好地反映出构造与金成矿的关系。粗粒破碎的黄铁矿含金较高，说明构造运动使金在黄铁 矿中进一步富集。不同期次的断裂充填物的微量元素分布特征研究同样说明了构造对金的富集起 到了十分关键的作用。Ｈｇ、Ｗ、Ｍｏ、Ｆ等微量元素在构造作用下的地球化学行为说明燕山期构造运 动对本区金的成矿仅仅起到了进一步富集的作用。  相似文献   

粤西阳春中生代钾玄质侵入岩及其构造意义：Ⅱ．微量元素和Sr—Nd同位素地球   总被引：36，自引：8，他引：36  

李献华  周汉文等 《地球化学》2001,30(1):57-65

粤西阳春地区马山二长闪长岩强烈富集K、Sr和LREE，（^87Sr/^86Sr)i ＝0．7046，εNd(t)≈ 1；岗尾－轮水岩体较富集K、Rb、Th和LREE，（^87Sr/^86Sr)i＝ 0．7063，εNd(t)≈－2；石录岩体较富集Sr,K、Rb、Th和LREE相对较低，（^87Sr/^86Sr)i＝0．7084－0．7089，εNd(t)≈－6。马山岩体来源于大离子亲石元素（LILE）和LREE富集的交代地幔；岗尾－轮水岩体来自于放射成因Sr、Nd同位素组成略高或交代时间略早的富集交代地幔，并且经历了明显的结晶分异作用；石录岩体则很可能是前存下地壳底垫基性岩重熔形成的。从早侏罗世到早白垩世，南岭西部的岩浆成分和源区的规律性变化反映了区域软流圈地幔上涌和岩石圈伸展－拉张－减薄的演化过程。  相似文献   

可控冲击矛偏转理论研究     

马新  熊青山  刘静 《世界地质》2001,20(2):202-205

偏心钻头在钻进的过程中轨迹呈曲线，而影响曲线曲率半径的原因是多方面的。在对冲击矛及土体做了若干假设的基础上建立起了冲击矛受力的力学模型，从力学的角度对可控冲击矛的钻进轨迹进行了深入的理论分析及研究，从本质上找出了可控冲击矛轨迹变化的根本原因。  相似文献   

强相关干扰的自动追踪消除法   总被引：2，自引：1，他引：2  

詹毅 《物探化探计算技术》2001,23(3):210-214

在信号分析中，有一类强相关干扰在频率上与有效信号相近，能量比有效信号更强，通常所用的频率滤波等方法都难以消除干扰，作者在本文中针对这种强相关干扰的特点提出了一种自动追踪消除法，即首先自动追踪相关干扰的方向，然后恢复其能量，再从实际获取的信号中减去相关干扰能量，即可得到所需的有效信号的能量。该方法在几个石油勘探地区的二维和三维地震资料中进行了应用，并获得了成功，作者在文中最后显示了一个地区的试算效果。  相似文献   

山东淄博地区上寒武统沉积地球化学特征及其层序地层学意义   总被引：4，自引：0，他引：4  

李振清  周洪瑞  陈建强 《现代地质》2001,15(4):377-382

根据微量元素和稳定同位素的特征可以推断古盐度、古水温和古水深 ,恢复古沉积环境 ,并判断海平面的相对变化。对淄博地区上寒武统微量元素Sr、Ba、V、Ni和氧 碳同位素的研究结果表明其属于稳定的浅海环境 ,微量元素和氧 碳同位素的变化趋势与海平面的波动有一定的对应关系 ,而且从地球化学方面为层序地层的划分提供了依据。研究结果也表明 ,由于沉积地球化学特征的复杂性 ,不能简单地用一种因素来分析。  相似文献