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131.
中国近海水域重金属的生物监测 总被引:2,自引:0,他引:2
本文对中国香港近海水域的铜、锌、铁、镉等重金属在纹藤壶(Balanus amph—itrite)、僧帽牡蛎(Saccostrea cucullata)、扁跳钩虾(Platorchestia platensis)体内积累的浓度作了比较分析,在大量的生物监测资料基础上,指出香港水域的重金属浓度在时间和地域上都存在着梯度。生物体内的重金属含量变化反映了香港地区重金属污染的基本特征。 相似文献
132.
重金属污染与人体健康 总被引:7,自引:0,他引:7
环境中与人类健康关系较密切的重金属有Hg、Cd、Zn、Cu、Cr、Pb等,它们在工业生产中,涉及到的行业多、用途广,但对人体容易产生危害。此外,重金属污染物进入环境后,不象有机污染物那样较易分解,而是长期残留于环境中,一旦进入人体,也不会在体内发生分解和变化。因此,对于重金属污染物对人体毒害,应当予以足够的重视。 相似文献
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135.
Heavy metals in surface sediments from Minjiang Esturary—Mazu and Xiamen—Jinmen sea areas 总被引:4,自引:0,他引:4
The concentrations of Cu,Pb, Zn and Cd in surface sediments from Minjang Estuary-Mazu and Ziamen-Jinmen sea areas of China were investigated during 1995-1996.The concentration ranges of Cu,Pb ,Zn and Cd in the Minjiang Estuary-Mazu sea area were 16.4-37.2,33.4-69.6,92.1-128,0.087-0.036mg/kg(dry wt.),respectively; those for Xiamen-Jinmen sea area were 11.0-24.5,36.0-80.3,77.5-161,0.135-0.285mg/kg(dry wt.), respectively.The concentration and distributions of Cu,Pb,Zn and Cd in surface sediments of Minjiang Estuary-Mazu and Xiamen-Jinmen sea areas were analyzed and evaluated.The results showed that the values of Zn and Pb exceeded those of sediment quality criteria.The average concentration of Cu in Minjiang Estuary-Mazu sea area was higher than that in Xiamen-Jinmen sea area.The obviously higher concentrations of Cu,Pb, Zn and Cd were found at outlets of Minjiang and Jiulong River.From the estuaries to open sea, the concentrations of Cu, Pb,Zn and Cd had a decreasing trend, and then elevated in the sea areas near Mazu and Jinmen, suggesting that Cu,Pb,Zn and Cd in Minjiang Estuary-Mazu and Xiamen-Jinmen sea areas may come from both the mainland and Taiwan of China. 相似文献
136.
A pot experiment was conducted to investigate the influence of elemental sulfur to contaminated soil on plant uptake by a heavy metal hyperaccumulator, Indian mustard( Brassica juncea ) and a field crop, winter wheat( Triticum. aestivum). Elemental sulfur(S) with different rates was carried out, they were 0(S0 ), 20(S20 ), 40(S40 ), 80(S80 ), and 160(S160 ) mmol/kg respectively. Extra pots with the same rates of S but without plants were used for soil sampling to monitor pH and CaCl2-extractable heavy metal changes. The results showed that S enhanced phytoextraction of Pb and Zn from contaminated soil. Application S effectively decreased soil pH down to 1.1 as the most at the rate of Sl60. The concentrations of CaCl2-extractable Pb and Zn in soil and uptake of Pb and Zn by the plants were increased with soil pH decreased. A good correlation between CaCl2-extractable Pb/Zn and soil pH was found( Rpb^2 = 0.847 and RZn^2 = 0,991, n = 25). With S application, soil CaCl2-extractable Pb and Zn concentrations, concentration of Pb and Zn in plants and the amount of removal by plant uptake were significanfly higher than those without S. Under the treatment of S160, the highest CaCl2-extmctable Pb and Zn were observed, they were 4.23 mg/kg and 0.40 mg/kg, 2.7 and 2.0 times as that of the control(So ) respectively. At the highest rates of S( Sl~0 ), both Indian mustard and winter wheat reached the highest uptake of Pb and Zn. The highest Pb concentrations in wheat and Indian mustard were 32.8 mg/kg and 537.0 mg/kg, all 1.8 times as that of the control, and the highest Zn concentrations in wheat and Indian mustard were 215.5 mg/kg and 404.0 mg/kg, 2.4 and 2.0 times as that of the control respectively. The highest removals of Pb and Zn from the contaminated soil were 0.41 rag/pot and 0.31 nag/pot by Indian mustard in the treatment of S160 through 50 days growth. 相似文献
137.
本文详细地介绍了Cu、Pb、Zn、Cd、Hg、Cr、Se等几种金属元素在土壤 -植物农业生态环境中的形态分布、迁移转化、富集累积及其对植物生长作用机理的规律 ,以及对其采取的防治措施的最新研究进展 ,指出应从源头上防治重金属元素对土壤 -植物系统的污染 ,建设绿色生态农业从根本上解决土壤生态系统的重金属污染 相似文献
138.
重庆市近郊蔬菜基地土壤和蔬菜中重金属的质量现状 总被引:45,自引:1,他引:45
通过对重庆市近郊蔬菜基地土壤和蔬菜中重金属的监测和评价得出:重庆市近郊蔬菜基地部分土壤受到 Cd和Hg的污染;部分蔬菜受到Pb和Cd的污染。 相似文献
139.
印刷线路板厂含铜污泥固化处理工艺研究 总被引:10,自引:0,他引:10
研究采用水泥作固化基材固化处理某印刷线路板厂酸性废水用石灰混凝所产生的含铜、锡、金的污泥 ,对固化块在不同 pH的水中重金属Cu2 +的浸出实验结果表明 :水泥固化处理该混凝污泥效果良好 ,控制合适的条件 ,可得到混合性能好、初凝时间适当、抗压强度较好的固化块。Cu2 +的浸出率低于允许浸出浓度。混凝过程中加入硫脲硅酸钠等助剂 ,可提高固化效果。研究还对几种不同配比的固化块抗压强度进行了探讨。 相似文献
140.