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431.
Several local surveys on the submerged vegetation have been conducted in past decades along the Finnish Baltic coastal areas. Surveys have been carried out by using various methods,which make the temporal comparisons of the results difficult.The need of a joint programme for coastal phytobenthic monitoringis emphasised by the Nordic Council of Ministers and HELCOM. TheFinnish coastal phytobenthic monitoring programme complements theBaltic HELCOM monitoring programme (COMBINE). It is primarily designed to reveal the effects of eutrophication. The programmeincludes general principles for selection of monitoring areas aswell as a proposal for monitored habitats, communities and species. The need of evaluated and tested field methods, datacollecting, interpretation and data storage are addressed in theQuality Assurance part. The cost-efficiency is secured by integrating the phytobenthos programme with the coastal water monitoring for obtaining the supporting data such like salinity,temperature and nutrients. In the design of the monitoring programme a special interest is paid on areas with high protection values such as Natura 2000 or HELCOM's BSPA (Baltic Sea Protected Areas) or on aspects that would support the implementation of the EU Water Framework Directive.  相似文献   
432.
简要论述了江苏省地震速报的历史、现状及计算机技术在地震速报中的重要作用。介绍了FDSP的功能、采用的主要技术以及在本次南黄海6.1级地震中的应用  相似文献   
433.
/ In 1991 and 1992, temperature, salinity, and fluorescence were measured by automatic continuous registration using instrumentation on a ferry crossing the southern North Sea daily along a transect between Zeebrugge, Belgium, and Hull, United Kingdom. The temperature ranged between 4 and 21 degrees C off the Belgian coast and between 6 and 17 degrees C in the middle of the transect. Salinity varied between 34 and 35.5 PSU in the offshore part of the transect, but showed much larger variation along the Belgian and UK estuarine coasts. Fluorescence, which was used as a measure of phytoplankton biomass, was highest at the continental coast and lowest near the English coast. Spring blooms of phytoplankton were found along the continental coast and in the channel-influenced water; in 1991 the blooms were denser than in 1992. Some summer blooms were also recorded. Water masses could be distinguished on the basis of salinity and fluorescence patterns. The general patterns in the data are compared with the literature and discussed in relation to river discharge, light penetration, and wind speed and direction. Finally, the value of automatic and frequent measurements of fluorescence for monitoring phytoplankton is compared with less frequent observations at selected stations. It is concluded that accurate information about phytoplankton biomass can only be established from the high-frequency data. KEY WORDS: Monitoring; Sampling; North Sea; Ferry; Fluorescence; Salinity; Temperature  相似文献   
434.
To understand nonylphenol (NP) contamination in the northeast coastal environment in China, NP was determined in 19 sediment and 20 bivalve samples collected during November 2005. NP was identified in all sediment samples in the range of 8.8 to 1.0 × 10 3 ng/g dw (dry weight), with an average of 0.12 × 10 3 ng/g dw. Most of the bivalve samples (oysters and mussels) contained detectable amounts of NP that ranged from ND (not detected) to 7.6 × 10 3 ng/g dw, with an average value of 0.79 × 10 3 ng/g dw. These results indicated that NP is ubiquitous in sediments and bivalves from the northeast coast of China, and are even present in bivalves sold as seafood. Serious contamination with NP was recorded off the coast of Bohai Strait and in semi-enclosed coastal environment such as Jiaozhou Bay and Liaodong Bay. Possible environmental and human health implications were understood in this study.  相似文献   
435.
基于AHP的南海海域渔业资源可持续利用评价   总被引:6,自引:0,他引:6  
根据渔业资源的特点和资料来源,采用层次分析法(AHP)提出了南海海域渔业资源可持续利用的评价指标体系,该指标体系包括渔业资源环境子系统、社会子系统和经济子系统等3个层次的23个指标。在此基础上,采用层次分析和专家咨询相结合的方法确定各指标的权重,并应用层次灰色综合模型评价了南海海域1978—2007年间渔业资源可持续利用状况。结果表明,近30年来,南海海域渔业资源利用水平呈逐步下降的趋势,1984年的综合评价值降至最低水平,仅为1978年的51.7%。1999年后渔业资源可持续利用水平开始波动上升,2007年的可持续利用水平为1978年的72.4%。综合评价的结果与现实情况较为符合,认为层次灰色综合评判模型应用于区域渔业资源可持续利用评价是可行的。文中并提出了加强人工鱼礁建设、增殖放流等水生生物资源养护和转变渔业经济方式等是提高南海海域渔业资源可持续利用水平的重要举措。  相似文献   
436.
Mercury (Hg) is present in the marine environment as a natural metal often enhanced through human activities. Depending on its chemical form, Hg can cause a wide range of immunotoxic e ects. In this study, the influence of methyl-, ethyl- and phenylmercury as well as mercurychloride on immune functions was evaluated. Two parameters of cellular immunity, proliferation and mRNA cytokine expression of interleukin-2, -4, and transforming growth factor , were investigated in harbor seal lymphocytes after in vitro exposure to Hg compounds. While all Hg compounds had a suppressive e ect on proliferation, di erences between juvenile and adult seals were found. Lymphocytes from juveniles showed a higher susceptibility to the toxic e ect compared to lymphocytes from adults. Furthermore, the degree of inhibition of proliferation varied among the four Hg compounds. The organic compounds seem to be more immunotoxic than the inorganic compound. Finally, for the cytokine expression of methylmercury-incubated lymphocytes, timedependent changes were observed, but no dose-dependency was found. Marine mammals of the North Sea are burdened with Hg, and lymphocytes of harbor seals may be functionally impaired by this metal. The present in vitro study provides baseline information for future studies on the immunotoxic e ects of Hg on cellular immunity of harbor seals.  相似文献   
437.
Water input requirements of the rapidly shrinking Dead Sea   总被引:1,自引:0,他引:1  
The deepest point on Earth, the Dead Sea level, has been dropping alarmingly since 1978 by 0.7 m/a on average due to the accelerating water consumption in the Jordan catchment and stood in 2008 at 420 m below sea level. In this study, a terrain model of the surface area and water volume of the Dead Sea was developed from the Shuttle Radar Topography Mission data using ArcGIS. The model shows that the lake shrinks on average by 4 km2/a in area and by 0.47 km3/a in volume, amounting to a cumulative loss of 14 km3 in the last 30 years. The receding level leaves almost annually erosional terraces, recorded here for the first time by Differential Global Positioning System field surveys. The terrace altitudes were correlated among the different profiles and dated to specific years of the lake level regression, illustrating the tight correlation between the morphology of the terrace sequence and the receding lake level. Our volume-level model described here and previous work on groundwater inflow suggest that the projected Dead Sea–Red Sea channel or the Mediterranean–Dead Sea channel must have a carrying capacity of >0.9 km3/a in order to slowly re-fill the lake to its former level and to create a sustainable system of electricity generation and freshwater production by desalinization. Moreover, such a channel will maintain tourism and potash industry on both sides of the Dead Sea and reduce the natural hazard caused by the recession.  相似文献   
438.
研究东中国海中日共同开发区附近海域溢油污染的问题,在模拟水动力场的基础上模拟了海上溢油漂移扩散情况。在表层流场和风场的作用下漂移,而油膜的扩展则通过油粒子的随机走动来实现。本文以东海西湖凹陷原油为溢油油种,通过模拟分析不同季节和不同风况下的溢油事故,对溢油油膜的扫海范围进行了分析。  相似文献   
439.
对东海内陆架表层沉积物中黑碳含量进行了分析,探讨了黑碳在东海内陆架不同区域的分布特征、影响因素及来源,并与长江口徐六径悬浮颗粒物中的黑碳进行了对比。结果显示,长江口徐六径悬浮颗粒物中黑碳的含量平均为1.68±0.51mg/g,且枯季浓度要高于洪季,这反映了燃烧活动的季节变化。黑碳在东海内陆架表层沉积物的分布具有明显的区域特征,近岸区域沉积物中的黑碳含量接近,且与粒径成负相关,并低于徐六径悬浮颗粒物中黑碳的含量,说明来自长江输入的黑碳主要以烟炱为主,并且部分粒径极小的颗粒未完全沉积下来;在123°E以东区域的表层沉积物中的黑碳含量分布较广,并与平均粒径成正相关,说明该区域主要以石墨态黑碳为主。另外,东海内陆架表层沉积物BC/TOC在0.11~0.55之间,因此在研究该区域碳循环过程中,不可忽视BC在不同区域的分布特征及类型差别。  相似文献   
440.
环渤海地区海域空间资源使用和供给分析   总被引:3,自引:0,他引:3  
从海域空间资源使用程度、结构和效益等方面,比较分析了环渤海地区的海域空间资源使用现状,并分析了环渤海地区的海域空间资源供给情况.根据分析结果,指出了环渤海地区的海域空间资源使用的比较优势,最后提出了环渤海地区海域空间资源使用和供给分析中有待解决的问题.  相似文献   
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