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Zooplankton play a core hub position in pelagic food webs, as they transfer the organic energy produced by primary producers to higher trophic levels. As the main driver of the marine biological pump, zooplankton greatly determine the amount and composition of vertical particle flux via rapid grazing and defecation. Distribution, life history, population properties and secondary production of zooplankton are greatly impacted by global climate change and human activities. Marine zooplankton are a highly diverse group that includes almost all nutrition modes and involves numerous ecological processes. Thus, it is difficult to simulate the transfer of energy to higher trophic levels in marine energy flow and biogeochemical models based on individual species. Recently, zooplankton functional groups were proposed, which is an ensemble average of schematic trophic behaviors and biogeochemical actions, and it has been applied to studies of marine food webs and biogeochemical cycles. In this book, we reported our research on the zooplankton functional groups in the Yellow Sea. The results could provide references for the study on the zooplankton functional groups in other sea areas.

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Yuanzi Huo, Associate Professor, College of Marine Ecology and Environment, Shanghai Ocean University, China; Visiting Scholar, University of Connecticut, USA; PhD, Institute of Oceanology, Chinese Academy of Sciences, China; B.S., Dalian Ocean University, China; Elected into member of 27th and 29th Chinese Antarctic Research Expedition.

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