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排序方式: 共有8133条查询结果,搜索用时 15 毫秒
1.
The coastal water of northeast Taiwan island, called 'Yin-Yang Hai' for its distinct yellow colour compared with blue offshore water, was investigated from 1989 to 1990 by the authors. Biological study showed the dominant species of plankton to be Copepoda, Cladocera, planktonic eggs and Diatoma. Dominant species of benthos were young crabs, Amphipoda and Annelida, with Amphipoda usually occurring in heavily polluted areas. Heavy metal data showed that the concentration of copper was high. the copper and iron concentration in algae of the intertidal zone was also high. the concentrations of iron and copper in inshore water were also higher than in offshore water. By comparison of the pH and salinity distribution of this area, we conclude that this coastal water has been polluted by acid waste water from coastal industry. the suspended solids concentration in sea water is high. Flocculation occurring at the boundary of fresh and saline water might be a reason for the distinct yellow colour of the water of this area. Further study is required. 相似文献
2.
Onianwa PC 《Environmental monitoring and assessment》2001,71(1):13-50
This article reviews the literatureon the use of mosses for monitoring atmospheric metalpollution. It discusses the nature of mosses, themechanisms for moss uptake of metals from the air andwet precipitation, the various forms in which mossesare used for this purpose, and cases in which mosseshave been used for monitoring local hot spots ofpollution, and regional patterns of metal pollution.Also highlighted are the questions of uptake of metalsfrom the substrates, interspecies differences, and acomparison of the effectiveness of mosses with otherindicator materials, among other issues. 相似文献
3.
Mulberry-silkworm food chain--a templet to assess heavy metal mobility in terrestrial ecosystems 总被引:1,自引:0,他引:1
Assessment of the food chain mobility of heavy metals inthe natural ecosystem receives more attention nowadays. Inthe present study, mulberry-silkworm food chain has beenfocused as a templet to assess the biomobility of heavymetals in soil-higher plant-insect hierarchy. Both in thecase of Cd and Cu treatments, higher mobility wasobserved in the level-1 (soil–root) followed by level-3(leaf–larva), level-4 (larvae–faecal) and level-2(root–leaf). Consequently, roots accumulated more amountsof Cd and Cu, with a limited transport to the leaves.Among the two metals (Cd and Cu) tested, in the plant,the transfer potential of Cd exceeds that of Cu. Whereasin the case of leaf–larval transfer, Cu precedes overCd. Accumulation of Cd and Cu in all the levels (1–4)tested showed a concentration dependent increase, except inthe level 4 (larva–faecal) of Cd treatment where adeclining trend was noticed. 相似文献
4.
5.
Tan Zhiqun 《环境科学学报(英文版)》1996,8(2):191-195
plane decaying leaves have been found capable of removing chromium and nickel ions from aqueous solutions. The removal efficiency depends upon the pH conditions, ions components and concentrations, and concentrations of leaves in media. The maximum removal for unique Cr6+ is about 7.5-8.0g/kg leaves at pH 4. 0, for unique Ni2+ about 2. 6g/kg at the region of PH5. 0-5.5. Under the described conditions nickel increases chromium uptake by plane decaying leaves from solution. 相似文献
6.
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
7.
8.
长江铜陵段表层水中重金属含量及存在形态分布研究 总被引:11,自引:0,他引:11
通过测定长江铜陵段枯、丰水期江水中cu、Pb、Zn和cd不同形态的含量,分析了4种金属在江水中的存在形态分布,不同水期含量变化,水中悬浮物对金属吸附能力大小,以及近20年来含量的变化情况。结果表明,长江铜陵段江水中各重金属总量丰水期时大于枯水期,重金属各形态含量之间均有差异:丰水期时,各金属会被悬浮物以不同的方式携带进入水体中,cu、zn、Pb以活跃态和稳定态为主,Cd以活跃态为主;枯水期时,Zn主要以溶解态和稳定态为主,Pb以稳定态方式被携带,而80%的Cu、Cd是以溶解态形式存于水中。悬浮物(丰水期)对重金属的吸附能力大小顺序为Pb>Cu>Zn>Cd。与近20年江水中的重金属背景值比较,长江铜陵段重金属含量有普遍升高的趋势。 相似文献
9.
Chemical Composition and Acidity of Rain at the Gulf of Iskenderun,North-East Mediterranean 总被引:1,自引:0,他引:1
The purpose of the present work was to investigate the chemistry of rain in the Gulf of Iskenderun, North East Mediterranean, Turkey. The Gulf region has a large number of industries. Main industries existing in the region are iron and steel works, fertilizer plants, a cement plant, and several medium and mini size steel mills in addition to the international pipe line terminals. This study aims to apportion the local sources contributing to the overall pollution of the region. To this end a precipitation sampling program was started in January 2000, and over 48 precipitation samples were collected from each of 5 stations located at Iskenderun city center, Iskenderun industrial zone, Payas city center, the campus of Iskenderun Technical College and the campus of Mustafa Kemal University. Samples were analysed for pH, NO3
+, Cl-. Ca, Al, Ba, Na, Cd, Co, Cr, Cu, Pb, Li, Mg, Mn, Ni, Zn, Fe, K. Concentrations of metal ions were determined by ICP-AES. NO3
- ions and pH were determined by using NO3
- selective electrode and pH meter, respectively.pH values of the collected samples at the industrial zone and at Payas city center, ranged between 5.02 and 7.38, respectively. NO3
- and metal ions concentrations were highly variable. Concentrations of Ca and Fe ions were higher in the industrial zone and Payas city center. In the other three stations, concentrations of metal ions and NO3
- ion were lower than that of industrial zone and the values of pH ranged between 6 and 7.4. The average pH values at Iskenderun Gulf showed that the precipitation was not acidic, because of the high concentration of Ca. The highest concentrations of Na and Cl ions were recorded in the University campus because the campus is located by the Mediterranean Sea. 相似文献
10.