Sai Elangovan S, Arun Kumar M, Karthik R, Siva Sankar R, Jayabarathi R, Padmavati G
Department of Ocean Studies and Marine Biology, Pondicherry University, Port Blair, Andaman, 744 103, India.
Aquat Biosyst. 2012 Aug 31;8(1):20. doi: 10.1186/2046-9063-8-20.
Microzooplankton consisting of protists and metazoa <200 μm. It displays unique feeding mechanisms and behaviours that allow them to graze cells up to five times their own volume. They can grow at rates which equal or exceed prey growth and can serve as a viable food source for metazoans. Moreover, they are individually inconspicuous, their recognition as significant consumers of oceanic primary production. The microzooplankton can be the dominant consumers of phytoplankton production in both oligo- and eutrophic regions of the ocean and are capable of consuming >100% of primary production.
The microzooplankton of the South Andaman Sea were investigated during September 2011 to January 2012. A total of 44 species belong to 19 genera were recorded in this study. Tintinnids made larger contribution to the total abundance (34%) followed in order by dinoflagellates (24%), ciliates (20%) and copepod nauplii (18%). Foraminifera were numerically less (4%). Tintinnids were represented by 20 species belong to 13 genera, Heterotrophic dinoflagellates were represented by 17 species belong to 3 genera and Ciliates comprised 5 species belong to 3 genera. Eutintinus tineus, Tintinnopsis cylindrical, T. incertum, Protoperidinium divergens, Lomaniella oviformes, Strombidium minimum were the most prevalent microzooplankton. Standing stock of tintinnids ranged from 30-80 cells.L-1 and showed a reverse distribution with the distribution of chlorophyll a relatively higher species diversity and equitability was found in polluted harbour areas.
The change of environmental variability affects the species composition and abundance of microzooplankton varied spatially and temporarily. The observations clearly demonstrated that the harbor area differed considerably from other area in terms of species present and phytoplankton biomass. Further, the phytoplankton abundance is showed to be strongly influenced by tintinnid with respect to the relationship of prey-predator. Consequently, further investigation on microzooplankton grazing would shed light on food web dynamics.
微型浮游动物由原生生物和小于200微米的后生动物组成。它展现出独特的摄食机制和行为，使其能够捕食体积达自身五倍的细胞。它们能够以等同于或超过猎物生长的速率生长，并且可以作为后生动物可行的食物来源。此外，它们个体并不显眼，但其作为海洋初级生产力的重要消费者却未得到充分认识。微型浮游动物在海洋的贫营养和富营养区域都可能是浮游植物生产的主要消费者，并且能够消耗超过100%的初级生产力。
于2011年9月至2012年1月对南安达曼海的微型浮游动物进行了调查。本研究共记录了19个属的44个物种。铃虫类对总丰度贡献最大（34%），其次依次为甲藻（24%）、纤毛虫（20%）和桡足类无节幼体（18%）。有孔虫数量较少（4%）。铃虫类有20个物种，分属于13个属；异养甲藻有17个物种，分属于3个属；纤毛虫有5个物种，分属于3个属。艾氏真铃虫、柱状拟铃虫、不定拟铃虫、叉状原甲藻、卵形洛曼虫、微小斯特龙虫是最常见的微型浮游动物。铃虫类的现存数量范围为30 - 80个细胞/升，并且呈现出与叶绿素a分布相反的分布，在污染的港口区域发现了相对较高的物种多样性和均匀度水平。
环境变异性的变化影响微型浮游动物的物种组成和丰度，其在空间和时间上存在差异。观察结果清楚地表明，港口区域在物种存在情况和浮游植物生物量方面与其他区域有很大不同。此外，就捕食者 - 猎物关系而言，浮游植物丰度显示出受铃虫类的强烈影响。因此，对微型浮游动物摄食的进一步研究将有助于揭示食物网动态。
