Mangrove sediments were sampled form 14 main mangrove reserves of China. Concentrations of Cu, Pb, Zn, Cr and Cd were analyzed with a PE ICP-MS, and physical and physicochemical factors such as particle size distribut...Mangrove sediments were sampled form 14 main mangrove reserves of China. Concentrations of Cu, Pb, Zn, Cr and Cd were analyzed with a PE ICP-MS, and physical and physicochemical factors such as particle size distribution, pH, salinity and Total Organic Matter （TOM） were also determined. In the mangrove sediments of China, the average contents of heavy metals decreased in the order ofZn 〉 Pb 〉 Cu 〉 Cr 〉 Cd. The average contents of heavy metals were： Cu = 22.8 4- 16.46 mg/kg, Pb = 76.1 4- 52.33 mg/kg, Zn = 86.3 4- 42.65 mg/kg, Cr = 18.4 4- 5.83 mg/kg and Cd = 0.21 4- 0.25 mg/kg. Compared with previous studies, levels of heavy metals increased greatly. Contents of Cd, Cu, Pb and Zn were higher than the Background Values （BV）. However, the contents of Cr was under the BV. The results revealed that levels of heavy metals changes significantly with anthropogenic input, physical and physicochemical factors. Significant correlations were found between concentrations of Cu, Ph and pH, TOM.展开更多
Heavy metal is a main pollutant in the marine ecosystem . so study on the effect of heavy metal on phytoplankton is important . Algae (Chaetoceros sp . , Dunaliella sp . ., Dicrateria zhanjiangenis Hu . var . sp .) we...Heavy metal is a main pollutant in the marine ecosystem . so study on the effect of heavy metal on phytoplankton is important . Algae (Chaetoceros sp . , Dunaliella sp . ., Dicrateria zhanjiangenis Hu . var . sp .) were laboratory cultured to observe the effect of heavy metals on their growth . The effect of different metal ion concentration , the detoxication effect of complexation agents and the growth of algae in different media and different nutrition levels were studied to evaluate the effect of metal speciation . It is proved that trace amount of heavy metals can stimulate the growth of algae cells but that high concentration is lethal . The sequence of toxicity is Cd2+】Zn2+】Pb2+ . In ordinary nutrition conditions , the detoxication sequence of complexation agents to Chaetoceros sp . is EDTA 】 sodium salicylate 】 sodium oxalate 】 sodium citrate 】 sulfanilic acid 】 O-phenanthroline . This is in good conformity with the stability constant sequence of these agents with copper and good evidence that展开更多
The effect of acid rain on spectes of Cu Pb. Zn and Cr has been studied by Tessler net method In simulart acld rain the content of Cu and Cr increased with decreasing pll. whereas solubiliztion content of Pb and Zn ha...The effect of acid rain on spectes of Cu Pb. Zn and Cr has been studied by Tessler net method In simulart acld rain the content of Cu and Cr increased with decreasing pll. whereas solubiliztion content of Pb and Zn has a peak value at pll= 3.5.4.5respectively which come from the exchangeable and carbonate-bound fractions in the first place. In addition, the content of varions species of Cu. Pb. Zn and Cr change greal in simalant acid rain. Copper transforms from superior fform (bound to organic matter ) to exchangeable, bound to carbonates and bound to Fe-Mc orldes while fead zine and chromiam transform from bound to Fe-Mn oxides to exchangeable and bound to carbocatesWith the development of industry. more Sox and more SOx and NOx are discharged into the air and the rainfall becomes caid this makes particulate metals more active and toxic.展开更多
Various species of Cu.Pb,Zn and Cr in dust of different origins and diameters were studied using Tessler scheme,and the partition law was revealed, The results indicated that superior form of Cu、Pb、 Zn and Cr was bo...Various species of Cu.Pb,Zn and Cr in dust of different origins and diameters were studied using Tessler scheme,and the partition law was revealed, The results indicated that superior form of Cu、Pb、 Zn and Cr was bound to organic master,bound to Fe-Mn oxides,bound to Fe-Mn oxides and residual.So their activity order was Zn>Pb>Cu>Cr.The exchangeable metals bound to carbonates and Fe-Mn oxides of four heary metals in small particles were superior to those in large particles,which illustrated that heavy metals in small paticles were more active and harmful.展开更多
基金This project is supported by National Natural Science Foundation of China （No. 41176090）.
文摘Mangrove sediments were sampled form 14 main mangrove reserves of China. Concentrations of Cu, Pb, Zn, Cr and Cd were analyzed with a PE ICP-MS, and physical and physicochemical factors such as particle size distribution, pH, salinity and Total Organic Matter （TOM） were also determined. In the mangrove sediments of China, the average contents of heavy metals decreased in the order ofZn 〉 Pb 〉 Cu 〉 Cr 〉 Cd. The average contents of heavy metals were： Cu = 22.8 4- 16.46 mg/kg, Pb = 76.1 4- 52.33 mg/kg, Zn = 86.3 4- 42.65 mg/kg, Cr = 18.4 4- 5.83 mg/kg and Cd = 0.21 4- 0.25 mg/kg. Compared with previous studies, levels of heavy metals increased greatly. Contents of Cd, Cu, Pb and Zn were higher than the Background Values （BV）. However, the contents of Cr was under the BV. The results revealed that levels of heavy metals changes significantly with anthropogenic input, physical and physicochemical factors. Significant correlations were found between concentrations of Cu, Ph and pH, TOM.
基金Project supported by the Fund of Excellent Young Teachers of State Educational Commission of China
文摘Heavy metal is a main pollutant in the marine ecosystem . so study on the effect of heavy metal on phytoplankton is important . Algae (Chaetoceros sp . , Dunaliella sp . ., Dicrateria zhanjiangenis Hu . var . sp .) were laboratory cultured to observe the effect of heavy metals on their growth . The effect of different metal ion concentration , the detoxication effect of complexation agents and the growth of algae in different media and different nutrition levels were studied to evaluate the effect of metal speciation . It is proved that trace amount of heavy metals can stimulate the growth of algae cells but that high concentration is lethal . The sequence of toxicity is Cd2+】Zn2+】Pb2+ . In ordinary nutrition conditions , the detoxication sequence of complexation agents to Chaetoceros sp . is EDTA 】 sodium salicylate 】 sodium oxalate 】 sodium citrate 】 sulfanilic acid 】 O-phenanthroline . This is in good conformity with the stability constant sequence of these agents with copper and good evidence that
文摘The effect of acid rain on spectes of Cu Pb. Zn and Cr has been studied by Tessler net method In simulart acld rain the content of Cu and Cr increased with decreasing pll. whereas solubiliztion content of Pb and Zn has a peak value at pll= 3.5.4.5respectively which come from the exchangeable and carbonate-bound fractions in the first place. In addition, the content of varions species of Cu. Pb. Zn and Cr change greal in simalant acid rain. Copper transforms from superior fform (bound to organic matter ) to exchangeable, bound to carbonates and bound to Fe-Mc orldes while fead zine and chromiam transform from bound to Fe-Mn oxides to exchangeable and bound to carbocatesWith the development of industry. more Sox and more SOx and NOx are discharged into the air and the rainfall becomes caid this makes particulate metals more active and toxic.
文摘Various species of Cu.Pb,Zn and Cr in dust of different origins and diameters were studied using Tessler scheme,and the partition law was revealed, The results indicated that superior form of Cu、Pb、 Zn and Cr was bound to organic master,bound to Fe-Mn oxides,bound to Fe-Mn oxides and residual.So their activity order was Zn>Pb>Cu>Cr.The exchangeable metals bound to carbonates and Fe-Mn oxides of four heary metals in small particles were superior to those in large particles,which illustrated that heavy metals in small paticles were more active and harmful.
