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1.
Kuang-Lung Fan 《Chemistry and Ecology》1992,6(1):213-224
The increasing use of sea water for industrial cooling presents a real threat to the ecological environment in the ocean. in Taiwan where many electric power plants along the coast take sea water for cooling, people are concerned seriously about nuclear power plants. There are three nuclear power plants in Taiwan. Each plant has two units for generating power. the first two are located along the northern coast of Taiwan. the third is located in Kenting National Park along the coast of southernmost Taiwan. the plants take sea water for cooling, and discharge their heated effluents to the ocean surface from the coast. the thermal effluents have variable effects on the ecological environment near the plants. Fishermen living near the power plants complain that the heated water affects the inshore fishery catch. in addition, the thermal water from the second plant is easily accumulated near the coastal zone to influence the nearby swimming area in the summer-time. the thermal water from the third plant bleaches or kills some corals in shallow water near the outlet, and this conflicts with the interests of Kenting National Park. 相似文献
2.
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
3.
本文利用统计分析和吸收系数描述了昆明西山土壤-植物系统中Fe,Mn,Ni分布特征。结果表明,受试植物在土壤-植物系统中对Ni元素均表现出相对的稀释和绥冲作用;对Mn元素,除了菊科夏田菊,山紫金子和牛旁外,均表现出相对富集作用。 相似文献
4.
排污收费制度在环境管理应用中存在的若干问题 总被引:4,自引:0,他引:4
简要总结了排污收费制度在上海环境保护管理工作中取得的6个方面的成绩,探讨了排污收费制度在实施过程中遇到的问题,对排污收费制度如何适应计划经济向市场经济的转变进行了讨论并提出了相应的建议。 相似文献
5.
对勐海县景真糖厂原料基地和各生产工段的生产状况进行了综合评价分析,探明了该糖厂生产中产生的"三废"排放特征,存在问题以及环境经济状况,提出了建立循环发展体系,进一步提高环境经济效益的措施建议。 相似文献
6.
头盔式面罩和头带式面罩性能的比较:头盔式面罩具有佩戴容易、气密性好。工艺简单,但舒适性差,视野不如头带式面罩好等特点;头带式面罩具有舒适性好,视野宽阔,但工艺较复杂,佩戴不易气密等特点。 相似文献
7.
在对不同企业之间的职业伤害风险进行量化和比较时,不同程度职业伤害的统一量化是关键难题。本文使用损失工作日的方法,通过对调研所得有效数据的统计学分析,计算得出企业职业伤害的重伤严重度系数α和轻伤严重度系数β的值,α和β值与国外相关研究结果有较好的可比性。本文所得到的α和β值是对不同企业职业伤害风险量化计算和比较的重要基础。 相似文献
8.
Marji J. Patz Katta J. Ready Quentin D. Skinner 《Journal of the American Water Resources Association》2004,40(5):1247-1255
ABSTRACT: The objective of this study was to examine the chemistry of Coalbed Methane (CBM) discharge water reacting with semi‐arid ephemeral stream channels in the Powder River Basin, Wyoming. The study area consisted of two ephemeral streams: Burger Draw and Sue Draw. These streams are tributaries to the perennial Powder River. Samples were collected bimonthly from three CBM discharge points and seven channel locations in Burger Draw and Sue Draw. Samples were also collected bimonthly from the Powder River above and below the confluence of Burger Draw. Before sample collection, the pH and electrical conductivity (EC) were measured in the field. Samples were transported to the laboratory and analyzed for alkalinity, major cations, and anions. From the measurement of sodium (Na), calcium (Ca), and magnesium (Mg), practical sodium adsorption ratio (SARp) and true sodium adsorption ratio (SARt) were calculated. Results suggest pH and EC of CBM discharge water was 7.1 and 4.3 dS/m, respectively. The CBM discharge water consisted of higher concentrations of sodium and alkalinity compared to other components. The pH of CBM discharge water increased significantly (p = 0.000) in the downstream channel of Burger Draw from 7.1 to 8.84 before it joined with the Powder River. Dissolved calcium concentration of CBM discharge water decreased significantly (p = 0.000) in the downstream channel water. Subsequently, SARp increased approximately from 24 to 29. The SARt also increased significantly (p = 0.001) in the downstream channel water. For instance, SARt of CBM discharge water increased from 32.93 to 45.5 downstream channels after the confluence of Sue Draw with the Burger Draw. The only significant difference in water chemistry above and below the confluence of Burger Draw with the Powder River was pH, which increased from 8.36 to 8.52. The significant increase in SAR values of CBM discharge water in Burger Draw and Sue Draw tributaries suggest a careful monitoring of salinity and sodicity is needed if CBM discharge water is used for irrigation in semi‐arid environments. Results discussed in this study will be useful to downstream water users who depend on water for irrigation. 相似文献
9.
通过模拟煅烧试验制取水泥熟料,参照JGJ 55-2000(《普通混凝土配比设计规程》)制取混凝土样品,参考SR003.1和NEN 7375浸出试验,分别研究液固比对粒状及块状混凝土样品中重金属(Cr、Ni和As)释放的影响。结果表明,在不同液固比条件下粒状混凝土中的重金属浸出浓度为Cr>Ni>As,Cr、As浸出浓度基本保持不变,分别为2 500 μg/L左右和5~6 μg/L,Ni在液固比(L∶S)<6时,浸出浓度随着液固比的增加而降低,在L∶S>6时,浸出浓度较稳定,为35.7~41.5 μg/L;浸出量均随着液固比的增加而增大。液固比(L∶S)<10时,块状混凝土中重金属累积释放量及扩散系数均随液固比的增加而增大,当L∶S>10时两者基本保持不变。 相似文献
10.