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71.
我国东南沿海3港口有机锡污染的调查   总被引:14,自引:1,他引:13  
利用顶空固相微萃取与气相色谱表面发射火焰光度检测法于2001年11月至2002年8月对我国东南沿海厦门、汕头和惠阳3个大型港口21个站位的水样、底泥和生物样的有机锡污染现状进行调查.结果表明,绝大多数样品的一丁基锡(MBT)含量最高,三丁基锡(TBT)次之,二丁基锡(DBT)大多低于检测限.水样的TBT含量实测值从低于检测限至9.8ng/dm3,泥样的为0.3~174.7ng/g(干重),生物样的为2.1~23.0ng/g(湿重).水样TBT含量均值以惠阳港的为最高,泥样和生物样的均以厦门港的最高.影响有机锡含量及其空间分布的主要因素有港口船舶吞吐量、水文状况、季节和与大型码头的距离.关联的海产腹足类性畸变调查结果发现,我国沿海有机锡污染比较普遍和严重,已对生态系统产生实质性的负面生态效应.  相似文献   
72.
胜利油田东营凹陷中央隆起带断层封闭模式研究   总被引:3,自引:2,他引:1  
东营凹陷中央隆起带断裂系统复杂,断层封闭性直接控制油气藏形盛分布及油气藏规模,封闭性强的断层附近可形成大规模油气藏,封闭性差的断层附近油气藏规模小,甚至无油气藏形成.以岩性配置封闭模式、主应力封闭模式和泥岩沾污带封闭模式3种最主要的封闭模式为例建立了东营凹陷中央隆起带断层封闭模式.定量分析评价了东营凹陷中央隆起带断层封闭性,认为东营凹陷中央隆起带封闭性断层的最佳断面正应力为40~50 MPa,封闭性断层的泥岩沾污因子常小于2.6.针对某一具体断层判断其是否具有封闭性需多方面综合分析,不可简单地进行单因素分析.   相似文献   
73.
利用MIKE21二维水动力模型,对海阳中心渔港建设前,以及两种预选方案建设后海域潮流分别进行数值模拟。在潮流模拟验证正确的基础上,建立了海底冲淤预测模型,预测了工程建设前后静风条件下全年冲淤趋势。并运用MIKE21Coupled ModelFM模块,模拟了极端天气条件(SE15m/s大风)浪流共同作用下工程附近海域的冲淤情况。根据方案建设前后潮流场、冲淤趋势进行分析,确定最优方案,为海阳中心渔港的规划设计提供决策参考。  相似文献   
74.
基于MIKE SA溢油模块,以燃料油为油种,建立了厦门西港海域溢油模型,模拟静风、主导风向(东北东风)和不利风向(西南风)3种风场条件下,一个潮周期内涨急、高潮、落急和低潮4个时段发生10 t溢油后油膜的漂移路径和影响范围.结果显示,发生在厦门西港海域的溢油在海面的漂移过程主要受潮流和风的影响,其中潮流起着主导作用.不同风向条件下,24 h内油膜的影响范围不同,静风条件下溢油浓度超一类(或二类,≥0.05 mg/dm3)、超三类(≥0.30 mg/dm3)和超四类(≥0.50 mg/dm3)的总影响面积分别为31.33、19.63和11.74 km2;主导风向条件下溢油浓度超一类(或二类)、超三类和超四类的总影响面积分别为99.62、69.01和8.99 km2;不利风向溢油浓度超一类(或二类)、超三类和超四类的总影响面积分别为8.38、5.05和2.10 km2.该预测结果可给出溢油事故发生后的影响范围、影响程度和影响敏感目标的时间,可为溢油事故应急决策的制定及溢油损害评估提供科学决策和支持,提升厦门海域环境风险管理应急能力建设.  相似文献   
75.
In a recent article in this journal (Butterworth and Richardson. A review of animal welfare implications of the Canadian commercial seal hunt. Marine Policy 2013;38:457–469), the authors argued that “generally accepted principles of humane slaughter cannot be carried out effectively or consistently during the Canadian commercial seal hunt”. The present review purports to show that these authors' conclusions were incorrect because they were highly selective in their treatment of the information available and made no attempt to consider other perspectives. In addition, their reliance on anecdotal video sequences to support some of their points was seriously flawed since a vast proportion of these sequences failed to meet fundamental criteria of scientific rigor. The article by Butterworth and Richardson [5] failed to provide an unbiased presentation of the available data and therefore did not bring further clarity to the debate on the Canadian commercial seal hunt.  相似文献   
76.
Body distribution and growth- and nutritional status-dependent accumulation of 21 trace elements were investigated in harbor seals (Phoca vitulina) stranded in the North Sea coast in 2002. Higher concentrations and burdens of Mn, Se, Mo, Ag, Sn, Hg, and Bi in the liver, Cd in the kidney, As in the blubber, and Co, Sr, and Ba in the bone were observed. Significant positive correlations of hepatic Se, Mo, Ag, Cd, Sn, Hg, Tl, and Bi with standard body length were found, while significant negative relationships were detected for Mn, As, Rb, Sr, and Sb in the liver. Concentrations of Co, Se, Sr, Sn, Hg, and Bi in the liver, V, Sr, Ag, Sn, and Hg in the kidney, V, Mn, Co, Rb, Sr, Sn, Ba, and Pb in the blubber increased with decreasing blubber thickness of harbor seals, indicating enrichment of these elements in the target tissue by emaciation.  相似文献   
77.
Eighty-five stranded or bycaught harbor porpoises collected from the Danish North Sea between 1980 and 2005 were analyzed for perfluorochemicals in the liver. PFOS was the predominant compound, making up on average 88.9% of the ∑PFC, followed by PFOSA (7.8%). PFUnA (1.9%) and PFDA (1.2%) were detected in most samples. PFHxS, PFNA and PFOA were only found in a minority of the samples. We found substantial differences in PFC concentrations among life history stages, the highest concentrations were found in neonates, suckling juveniles and lactating females. Such differences should be considered when PFC levels in wildlife are evaluated. The high concentrations found in young porpoises are of concern as PFCs have known toxic effects on the development of the central nervous system and reproductive organs. Despite efforts to reduce PFC emissions, a decreasing temporal trend of concentrations was not detected for any compound. PFCA concentrations were found to be increasing.  相似文献   
78.
A complex controversy emerged when the grey seal population in the Baltic Sea recovered after decades of stagnation. The seals now cause substantial economic losses to coastal fisheries. The paper analyses the attempts taken in Finland to mitigate the problems of fishermen. The mitigation attempts include the hunting of seals, fishing technology development, economic compensations and more comprehensive management approaches. These measures are discussed in light of the long-term sustainability and adaptability of a coastal fishery. This question is important with respect to further discussions on the possibility of the coastal fishery’s co-existence with seals and sheds light on more general goals for the adaptability in the management of social–ecological systems. The paper concludes that the more comprehensive measures taken have acknowledged the need to enhance the fishery’s adaptability, but the managerial approach they represent falls short of the requirements for successful adaptive management, especially in terms of embedding the management into specific coastal contexts.  相似文献   
79.
烟台市龙口港污损生物生态研究   总被引:1,自引:0,他引:1  
于2007年03月22日至2008年03月21日在山东省烟台市龙口港附近海域,进行了为期1年的挂板试验,本次调查共记录该海域污损生物32种,优势种为内枝多管藻(Polysiphonia morrowii)、软丝藻(Ulothrix flacca.)、肠浒苔(Entermorpha intestinalis)、中胚花筒螅(Tubularia mesembryanthemum)等.该海域全年均有污损生物附着,月板平均生物量为525.18 g/m2,5-11月的生物附着量较高,最高值出现在7月;季板平均生物量为1569.39 g/m2,生物群落的种类组成和生物量变化明显,其中秋季板生物量最高,龙口海域污损生物的附着种类受季节性水温变化的影响比较明显,藻类开始附着的温度低于动物.4个季度污损生物的种群多样性指数(H忆)春季最高,均匀度指数(J)和种群丰富度指数(M)则夏季最高.统计分析表明,龙口港海域污损生物群落可大致划分为 4个组群,秋季附着的污损生物代表了试验海域的主要特征,同时揭示出污损生物附着季节、演替时间长短等是影响群落种类组成的重要因素  相似文献   
80.
During 1966 and 1967, paraquat was applied on three occasions at 2 ppm for 30 min to control aquatic weeds in the South Branch experimental stream, a tributary of the lower Waimakariri River, Canterbury, South Island, New Zealand. Effects on the invertebrate fauna of the stream were studied before, during, and after the applications, by Surber and drift‐net samples.

After a heavy initial kill, the paraquat treatment reduced the number of amphipods caught in the drift fauna to 5% of the pre‐treatment level, and there was a slight reduction in the numbers of hemipterans. The total numbers in Surber samples increased markedly a year after treatments ended, mainly due to increased numbers of trichopterans.  相似文献   
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