Functional analysis of food web of pelagic plankton communities

目前利用优势物种信息分析生态系统的结构和功能，是利用特定生态系统中的整个物种信息来评价其有效性所必需的。本研究在热带、亚热带和亚北极地区的远洋浮游生物生态系统中进行，由于水生生态系统在较小尺度上具有良好的同质性，因此对物种、生物量和营养关系的必要数据采集可能比其他类型的生态系统更容易。然后，对每个群落的浮游生物种类和生物量的数据进行了挑战，要求完全收集，并构建了食物网络结构。根据热带、亚热带和亚北极表层浮游生物生态系统中物种及其生物量的信息，根据各功能类群的个体大小差异，将所有物种及其生物量划分为不同的分类类群。然后根据“较小的生物体总是被较大的生物体吃掉”的生态作用来构建食物网。这种类型的食物网结构最初是在本研究中提出的，并表明浮游生物群落的功能受物种、个体大小、生物量和食物链关系的影响，这在目前基于优势物种的分析中没有显示出来。海洋中深层群落缺乏初级生产者，仅受异养过程的控制，异养过程已经以物种、大小和每种生物量的形式合成，但其食物网分析被推迟到未来。

Current understanding of structure and function of ecosystem analyzed by use of information on dominant species is needed for its evaluation of validity by use of information of entire species in a given ecosystem.The present research was then conducted in pelagic plankton ecosystems in tropical, sub-tropical and sub-arctic regions where necessary data sampling on species, biomass and trophic relations is probably easier than the other types of ecosystems because of excellent homogeneity in rather small scale in aquatic ecosystem. Then data on species and biomass of plankton in each community were challenged to entirely collected, and constructed the food web structure. Data were synthesized either in epi-pelagic community having both autotrophic and heterotrophic processes or middle and deep depths having only heterotrophic processes.Based upon information on species and its biomass collected in tropical, subtropical and subarctic epi-pelagic plankton ecosystems, all species and its biomass were grouped in different compartments based upon individual size differences in each functional group for each taxonomic group. Food web was then constructed according to the ecological role of "the smaller size organisms are always eaten by the larger size organisms". This type of food web structure has been originally proposed in this study, and has shown that plankton community is functioning by species, individual size, biomass and food chain relationship which is not shown in the current analysis based upon dominant species.Middle and deep depth communities in the ocean lack primary producer and is solely controlled by heterotrophic processes, which have been synthesized in the form of species, sizes and each biomass, but its food web analysis has been postponed in the future.