4 resultados para tradescantia pallida

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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An extensive literature survey of over 17 Journals was carried out on Chinese sponges and their natural products in the period from 1980 to 2001. This review is thus intended to provide the first thorough overview of research on marine sponges from China Ocean territories. Information is provided about the rather-limited taxonomic study of Chinese marine sponges, with an analysis on their distribution and diversity. Research findings on the natural products and their bioactivity screening from Chinese sponges are summarized. The weaknesses, gaps and problems in the past R&D program of Chinese sponges are identified, which point to the future opportunities in exploiting these huge untapped sponge resources. The report is expected to serve as an entry point for understanding Chinese sponges and for furthering R&D on their bioactive compounds for new drug development. (C) 2003 Elsevier Science B.V. All rights reserved.

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本论文研究了渤海,胶州湾和东海20-200 μm微型浮游动物(桡足类幼虫、纤毛虫)的数量和生物量(1% Lugol's 试剂固定1000ml,Utermohl法150倍显微镜检查),在渤海和东海用稀释法(Landry and Hassett, 1982; Burkill et al., 1990)估计了微型浮游动物(<200 μm)对浮游植物的摄食压力。对上述海区调查的时间如下:渤海:1997年6,1998年6月(莱州湾),1998年10月;胶州湾1997年8、11月,1998年2、4、8、11月,1999年2月;东海:1998年7月。结果如下:渤海:1997年6月,只发现一种砂壳纤毛虫,数量为0-980个/L。1998年6月(莱州湾),微型浮游动物数量为30-2390个/L,生物量为1.5-25 μg C/L,水体中生物量为0.1-53.2 mgC m~(-2)。共有13种砂壳纤毛虫和一种无壳纤毛虫。纤毛虫的数量为0-2380个/L,生物量为0-24.52 μg C/L。纤毛虫优势种有无壳纤毛虫、Tintinnopsis pallida、T. amoyensis和T. chinglanensis。微型浮游动物的各个类群呈斑块分布。1998年10月,微型浮游动物的数量为0-770个/L,生物量为0-12.3 μg C/L,水体中生物量为0-136 mgC m~(-2)。在两次大面调查间隔的6天内,发生大风。两次大面站调查海区的温盐分布格局没有很大变化,但微型浮游动物的变化却十分显著,这也反映了恶劣天气对海洋生物的影响。在几个连续站对微型浮游动物的连续监测表明,微型浮游动物的分布与水团有很大关系。胶州湾:桡足类幼虫在8月数量最大(850个/L)。共记录两种无壳纤毛虫和7种砂壳纤毛虫。微型浮游动物数量弯化很大,从10-22600个/L。微型浮游动物的分布格局可能是湾内和湾外海水混合的结果:1997年11月,无壳纤毛虫No.12从湾外涌入,其他航次无壳纤毛虫No.11在湾内发生,向湾外扩散。东海:微型浮游动物数量较少,最大数量为1970个/L,绝大多数站位低于300个/L,生物量为0.08-45 μg C/L,水体50m积分生物量为5-283mgC m~(-2)。微型浮游动物有明显的斑块分布,连续监测没有发现明显的变化。根据稀释培养的结果,微型浮游动物对浮游植物摄食压力如下所述:渤海三个航次的微型浮游动物对浮游植物摄食率为0.13-1.01d~(-1),每天摄食浮游植物生物量(现存量)的12-49%,初级生产力的34-267%。东海稀释培养的结果为微型浮游动物地浮游植物的摄食率为0.2-1.2d~(-1),每天摄食浮游动物生物量的20-71%,摄食初级生产力的54-98%。由于稀释培养实验的设计和操作有许多争议之外,本文只将结果列出,对方法不作讨论。

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The abundance and biomass of ciliated protozoa and copepod nauplii were investigated at 21 grid stations and two anchored stations in the Laizhou Bay, Bohai Sea, China in June 1998. Dilution incubations were carried out to investigate micro-zooplankton grazing pressure at the anchored stations during spring tide and neap tide. The dominant species were Tintinnopsis amoyensis, T. chinglanensis, T. pallida and aloricate ciliates. A total of 13 species of tintinnids were found. The total abundance of ciliates and nauplii ranged from 30 to 2390 ind l(-1) at grid stations. Tintinnopsis amoyensis was the only ciliate found at the anchored stations and in concentrations which varied from 0 to 6700 ind l(-1). The spatial distribution of ciliates was patchy. Tintinnopsis amoyensis and T. pallida were distributed in the Weihe River mouth and Xiaoqinghe River mouth respectively. The aloricate ciliates, T. chinglanensis and Codonellopsis ostenfeldi dominated offshore in sequence. The water mixing process may affect the spatial pattern of the dominant ciliate species. The abundance and biomass of copepod nauplii were in the range of 0-140 ind l(-1) and 0-7 mu g C l(-1) respectively, with the peak appearing at grid station 15. The total biomass of ciliates and copepod nauplii was in the range of 1(.)5-25 mu g C l(-1). Water column biomass of ciliates and nauplii varied from 2(.)37 to 52(.)3 mg C m(-2). At the anchored stations, the phytoplankton growth rates ranged from undetectable to 0 21 d(-1) and micro-zooplankton grazing rates from 0 13 to 0(.)57 d(-1). The grazing pressure of micro-zooplankton were 12 to 43% of the chlorophyll standing stock and 84 to 267% of the chlorophyll (C) 2000 Academic Press.