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81.
A total of six nuclear reactors installed in three power plants, two along the northern and one along the southern coasts of Taiwan, started their operations one after another since October 1977. Owing to the large quantities of cooling water intake into and discharge from the plants, some environmental factors such as water temperature, chlorine, environmental radioactivity and nearshore currents may be significantly changed. Variations of these abiotic environmental factors may influence the biological activities in the ecosystem, particularly doing some kinds of damage to marine biological resources. Therefore, the possible environmental impact upon the biological systems including the fishery resources along the northern and southern coasts of Taiwan should be studied before and during the plant operation.

We have started the long-term programmes of biological, chemical and hydro-graphical surveys of the nuclear power plant sites on both northern (since July 1974) and southern (since July 1979) coasts of Taiwan. the survey items include ocean currents, physical and chemical properties of sea water, primary productivity, specific compositions and interspecific relationships among phyto- and zooplankton, algae, invertebrates, corals, and fishes; and radionuclides in water and biological specimens, and fishery statistics. in general, except for a few events, the operations of the six units of nuclear power plants have not produced detectable effects on the marine ecosystem. Radio activity levels and radionuclides in water and the biological specimens remained the same as background levels throughout the survey period. However, the events of coral bleaching and fish body anomalies caused by thermal discharges were observed respectively along the outlets of third and second Nuclear Power Plants. the purposes of this paper are to report and evaluate these two events during the operations of nuclear power plants in Taiwan.  相似文献   
82.
Abstract: Marine protected areas (MPAs), including no‐take marine reserves (MRs), play an important role in the conservation of marine biodiversity. We document the status of MPAs and MRs in Latin America and the Caribbean, where little has been reported on the scope of such protection. Our survey of protected area databases, published and unpublished literature, and Internet searches yielded information from 30 countries and 12 overseas territories. At present more than 700 MPAs have been established, covering more than 300,000 km2 or 1.5% of the coastal and shelf waters. We report on the status of 3 categories of protection: MPAs (limited take throughout the area), MRs (no‐take throughout the area), and mixed‐use (a limited‐take MPA that contains an MR). The majority of protected areas in Latin America and the Caribbean are MPAs, which allow some or extensive extractive activities throughout the designated area. These 571 sites cover 51,505 km2 or 0.3% of coastal and shelf waters. There are 98 MRs covering 16,862 km2 or 0.1% of the coastal and shelf waters. Mixed‐use MPAs are the fewest in number (87), but cover the largest area (236,853 km2, 1.2%). Across Latin America and the Caribbean, many biogeographic provinces are underrepresented in these protected areas. Large coastal regions remain unprotected, in particular, the southern Pacific and southern Atlantic coasts of South America. Our analysis reveals multiple opportunities to strengthen marine conservation in Latin America and the Caribbean by improving implementation, management, and enforcement of existing MPAs; adding new MPAs and MRs strategically to enhance connectivity and sustainability of existing protection; and establishing new networks of MPAs and MRs or combinations thereof to enhance protection where little currently exists.  相似文献   
83.
王强  王琪  周全法 《环境工程》2012,(3):89-92,95
印刷电路板废粉末料的资源化和无害化问题日益得到重视。以报废印刷电路板经机械粉碎和分选后的非金属粉(铜含量1%~5%)为原料,采用"氨浸—脱氨—干燥"的工艺制备碱式碳酸铜,设计了实验装置,考察了氨浸分离工艺条件,通过实验验证了其可靠性:铜的回收率达到98.8%以上,获得了纯度不小于98.0%的碱式碳酸铜,采用X射线粉末衍射(XRD)﹑扫描电镜(SEM)和能谱(EDS)方法对产品进行了分析和表征。  相似文献   
84.
吴飞  张福栋  王训  李秋华  江帆 《中国环境科学》2019,39(11):4776-4784
本研究以青藏高原典型海洋性冰川的雪冰-径流水为研究对象,分析讨论了雪冰-径流水中汞浓度变化趋势及控制因素.结果表明,贡嘎山冰川中雪、冰样品的THg浓度略高于全球背景值,而明永冰川以及米堆冰川的雪、冰、水样品均处于全球背景水平.3个冰川所有雪样、冰样、水样的THg浓度平均值分别为(4.78±5.99)ng/L、(1.72 ±1.15)ng/L、(1.31±0.91)ng/L.不同的环境介质中THg浓度变化总体表现为:雪 > 冰 > 水,其主要受颗粒汞沉淀作用及气态单质Hg挥发作用的控制.贡嘎山的径流水中THg浓度表现为六月最高(7.48±2.22)ng/L,十一月最低(1.39 ±0.27)ng/L.所有雪冰-径流水体系中HgP与THg存在极显著的正相关关系,雪中HgP/THg最高,其次为冰,最低为径流水.贡嘎山径流水中的HgP/THg及月均THg输出变化趋势受径流量和降雨量的影响.主成分分析表明了本研究区域雪冰中THg浓度主要受大气颗粒物沉降及季风传输的影响.此外,相比于其他2个冰川,贡嘎山冰川由于更加靠近人类活动密集区域,更易受到人类活动的影响.  相似文献   
85.
依据2011年2月~2016年1月在连云港近岸海域进行的19个季节航次海洋环境综合调查结果,分析探讨了该海域主要海水要素的季节变化趋势和相关性,结合历史资料阐述和评价了海域的营养状态水平、环境质量现状及变化趋势,对存在的环境问题进行了分析.结果表明:研究海域水质状况总体良好;水质评价结果显示无机氮(DIN)是海域内最主要的环境污染因子,且DIN含量近年来有逐渐增加的趋势,年均值已经超过二类海水水质标准;此外其他环境污染因子是活性磷酸盐(DIP)、化学需氧量(COD)和油类.调查期间研究海域处于富营养化状态,潜在富营养化分析显示氮磷比值(N/P)有逐渐增加的趋势;绝大多数季节的有机污染状况为轻度污染状态.研究结论对科学、系统的认识和评估连云港近海生态环境现状及预测未来生态环境变化趋势具有重要的参考价值,对连云港近海海洋生态环境的可持续发展具有十分重要的科学意义和实际应用价值  相似文献   
86.
目的 考察可剥涂层在海洋大气环境下的大型工程建造中的临时防护作用。方法 对来自两个厂家的可剥涂层进行了为期12周的耐候性试验,对可剥涂层在不锈钢及碳钢/环氧两种基底上的可剥离性、防护性和氟氯残留量进行了测试。结果 两个厂家的涂层在外观、耐蚀性、附着力等方面的试验结果没有明显差异,涂层的剥离强度均低于0.05 kN/m,涂层剥离后不锈钢表面的氟氯离子残留量远低于15 ?g/dm2,试验周期内环氧漆色差变化较小。结论 两个厂家的可剥涂层在光泽、硬度和剥离强度等测试方面的结果上存在差异,但对环氧漆均有着较好的防护作用,试验期内剥离性良好,且无有害化学元素残留,具有较高的工程应用价值。  相似文献   
87.
目的 针对不同设计使用年限的导管架平台,通过对比新型阳极和常规阳极用量来评价新型阳极的优势和不足。方法 针对设计寿命15年和30年的导管架平台,计算满足不同阶段保护电流需求的新型阳极和常规阳极的需求量。结果 当导管架平台设计年限较短,比如15年,牺牲阳极用量由初期保护电流需求量决定,新型阳极的使用可以达到节约阳极用量的目的。当设计年限较长,比如30年,牺牲阳极用量则由维持电流需求量决定,采用新型阳极并不能节约阳极用量。结论 并非所有设计年限的导管架平台使用新型阳极都能达到节约用量的目的,具体要根据实际计算结果而定。  相似文献   
88.
The National Oceanic and Atmospheric Administration's (NOAA) National Status and Trends (NS&T) Programme has analyzed samples of surface sediment collected at almost 300 coastal and estuarine sites throughout the United States since 1984. the overall distributions for concentrations of each element are approximately lognormal allowing a definition of geometric means and of “high” concentrations as those exceeding the mean plus one standard deviation of the lognormal distribution. Those mean and “high” concentrations should be useful for comparing the NS&T data set and with other reports on sediment contamination. A world-wide data set, constructed from data in the literature, was summarized in an identical manner. It was found, after excluding locally extreme values, that the NS&T and world-wide data sets yielded very similar mean and “high” concentrations for Cu, Ni, Pb and Zn. Chromium was the sole element showing higher summary statistics in the NS&T data set, a result attributed to NS&T sampling in areas of naturally (not contaminated) elevated Cr content. It remains undetermined, however, why the world-wide data set, even with exclusion of “hot spots”, yielded higher means and “highs” for Cd, Hg, As, and Ag.  相似文献   
89.
Disposal of sewage sludge in the New York Bight Apex (12-Mile Dump Site) ceased at the end of December 1987. Previous efforts to quantify the effects of sludge were hindered by the inability to obtain true replication. the cessation of dumping afforded the opportunity to apply the technique of replication in time, also known as a Before/After, Control/Impact design. Conditionally, this method allows one to separate treatment effects from the natural differences that confound many environmental impact studies. the Environmental Processes Division of the Northeast Fisheries Center, National Marine Fisheries Service sampled the benthic environment of the New York Bight Apex from June 1986 through September 1989 using a sample design based on the technique of replication in time.

Three dominant species (rock crab, Cancer irroratus; little skate; Raja erinacea; and winter flounder, Pseudopleuronectes americanus) and total demersal finfish, collected by otter trawl, showed no statistically significant response to the cessation of disposal. American lobster (Homarus americanus) increased in local abundance, but this result was possibly confounded by a change in fishing effort.  相似文献   
90.
Impact of anions on the heavy metals release from marine sediments   总被引:2,自引:0,他引:2  
Marine sediments from Lianshan Bay in Huludao, China, were studied in laboratory. A series of simulated experiments were carried out to investigate the influences of three kinds of anions CL^-, SO4^2- and HCO3^- on the release ofCd, Pb, Cu and Zn from the sediments. The results showed that the sequences about the impact of the three anions were Cl^-〉HCO3^-〉SO4^2+. The release potential of heavy metals in the presence of each anions was in the following order: Cd≥Cu 〉Zn≈Pb. The correlations were positive between CI content and the quantity of Cd released from the marine sediment, whereas there was no significant relationship between CI content and amount of Cu and Zn released. For SO4^2- and HCO3^-, the release of the heavy metals from marine sediments was not obvious.  相似文献   
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