【摘要】 超微型浮游植物(大小为0.2～2μm)在海洋生态系统中起着关键作用,也是海洋生态系统能量流动和物质循环的重要组成部分,特别是在寡营养海区初级生产力方面起着主导地位,对硅、碳颗粒物在大洋深层的输出具有重要意义。目前对超微型浮游植物的研究还远远落后于实际需要,主要是因为该类群难以分离培养、鉴定和定量测定。迅游藻(Bolidophyceae)是超微型浮游植物中的一类真核生物,它包括迅游单胞藻目(Bolidomonadales)和帕玛藻目(Parmales)。尽管迅游藻对浮游植物群落的细胞丰度贡献相对较小(<0.1%),但是其分布广泛,是沿海和上升流区域中最丰富的浮游植物类群之一,普遍存在于热带到极地海洋生态系统中。迅游藻是系统发育上最接近硅藻的原生藻群,不同的是迅游藻细胞壁没有全部的硅质化。本文阐述了迅游藻的研究现状,总结了迅游藻的发现,以及近年来通过对迅游藻系统发育(基于SSU rDNA和rbc L基因的序列分析)、生态学和生理学研究获得的最新信息,详细说明了迅游藻作为硅藻姊妹群的分类学地位,对于厘清这些硅化藻类之间的进化联系有重要意义。同时还强调了迅游藻在海洋硅碳循环中的作用,对海洋超微型浮游植物在全球生物地球化学循环中的地位做出了进一步的说明。更多还原

【Abstract】 Picophytoplankton(0.2～2 μm) is an important part of the energy flow and material cycle of marine ecosystems,thus plays a key role in marine ecosystem. Picophytoplankton contributes greatly to primary productivity in oligotrophic waters, which is of great significance to the export of silicon and carbon particulates in the deep ocean. At present, the research on picophytoplankton can not meet the actual needs, because it is difficult to culture, identify and quantify. Bolidophyceae is a group of picoeukaryotes, including Bolidomonadales and Palmales. Although the contribution of Bolidophyceae to phytoplankton abundance is small(< 0.1%), it is widely distributed and is one of the most abundant phytoplankton in coastal and upwelling regions. Bolidohyceae spreads widely throughout marine ecosystem, from tropical to polar regions. Bolidophyceae is the Stramenopiles group phylogenetically nearest to the diatoms. Unlike diatoms, Bolidophyceae cell walls are not completely silicified. This paper describes the state of art of Bolidophyceae, summarizes its discovery, and the current information on taxonomy(sequence analysis based on SSU r DNA and rbc L genes), ecology and physiology. It explains in detail the taxonomic status of Bolidophyceae as a sister group of diatoms, which is also important to clarify the evolutionary relationship among these silicated alga. At the same time, this paper also emphasizes the role of Bolidophyceae in marine silicon-carbon coupling cycle, and further explains the status of marine picophytoplankton in the global biogeochemical cycle.更多还原