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181.
From 1980 to 1998, biofouling communities in Hong Kong waters, the Zhujiang RiverEstuary and the Mirs Bay were studied and a total of 610 samples. The samples were collected from vessels, buoys, piers and cages. Totally, 340 species (see Appendix I ) have been recorded and identified, six of which are new. At the same time, research on the biology of the cirripede, bryozoan, polychaete and mollusc communities were also conducted. Twenty-three related papers have been published. This review summarizes works in Hong Kong over past twenty years, and some unpublished data are also reported.  相似文献   
182.
A useful radiance-converting method was developed to convert the Landsat-7 ETM+thermal-infrared (TIR) band’s radiance (Lλ,L7/ETM+) to that of Landsat-5 TM TIR (Lλ,L5/TM) as: Lλ,L5/TM=0.9699xLλ,L7/ETM++0.1074 (R2=1). In addition, based on the radiance-converting equation and the linear relation between digital number (DN) and at-satellite radiance, a DN-converting equation can be established to convert DN value of the TIR band between Landsat-5 and Landsat-7. Via this method, it is easy to integrate Landsat-5 and Landsat-7 TIR data to retrieve the sea surface temperature (SST) in coastal waters on the basis of local empirical algorithms in which the radiance or DN of Lansat-5 and 7 TIR band is usually the only input independent variable. The method was employed in a local empirical algorithm in Daya Bay, China, to detect the thermal pollution of cooling water discharge from the Daya Bay nuclear power station (DNPS). This work demonstrates that radiance conversion is an effective approach to integration of Landsat-5 and Landsat-7 data in the process of a SST retrieval which is based on local empirical algorithms.  相似文献   
183.
The fish and macro-crustacean community of the Vaccarès lagoon (Rhône River delta, South France) was sampled monthly from 1993 to 2002. The lagoon salinity shifted from 15 in 1993 to 5 in 1994–1997 and went back to 15 in 1999–2002. Connections with the sea also varied during the study period with larger openings in 1996–1997. During the study period, the community changed to revert in 2002 to a state similar to 1993. These changes consisted of a sequence of increased and decreased patterns of freshwater species and some marine species. Typical lagoon species tended to resist to salinity changes. Freshwater species colonised the lagoon when the salinity was low. Marine species may have varied both in relation to connections with the sea and to indirect effects of freshwater outflow. This study shows that community changes following environmental variations can be delayed in time, and emphasises the need for long-term studies.  相似文献   
184.
渤海鱼类群落结构特征的研究   总被引:16,自引:2,他引:16  
根据1982-1985年和1992年8月-1993年6月间渤海渔业增殖生态学调查所得的1090网次定量资料,运用数理统计的方法,分析鱼类群落结构多样性综合指标的变化特征。结果表明,在1982-1985年间渤海鱼类鱼种数为119种,其中暖温种居首位,占57.98%;暖水种次之,占28.57%;冷温种种数最少,占13.45%。群落结构的季节变化规律呈现单周期型,10月份鱼种数最多,达83种;2月份仅为  相似文献   
185.
A small, simple and inexpensive device is described which allows the sampling of waters with a minimum of disturbance. This is particularly important when determining near-surface profiles, for example, following a dye release.  相似文献   
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福建海洋兽类及其分布   总被引:4,自引:1,他引:4  
李树青 《台湾海峡》1997,16(4):479-485
通过对在福建沿海地下发掘出土的海兽骨骼,古文献比较分析研究,提出了福建省古代7种海兽分布名录;依据采集和调查到的现生海兽标本,提出了福建省18种海兽的种类和分布。  相似文献   
190.
Abstract. The body organization and some biological data of Epimenia arabica , a new species of Sotenogastres of the order Cavibelonia , are presented. The species is described based on four large-sized specimens (13–21 cm × 0.7-1 cm) from three different localities off the coast of the Sinai Peninsula (Red Sea). It feeds on Scleronephthya corymbosa V erseveldt & C ohen ( Octocorallia: Alcyonacea ), generally at depths of 2–5 meters.  相似文献   
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