Phytoplankton biomass, chlorophyll concentration, and variability of lipid content in Calanus euxinus in the Black Sea in June 1991

During field studies relationships between chlorophyll concentrations, phytoplankton biomass (total, individual sizes and species) and level of accumulation of total lipids, wax esters, triacylglycerols, and phospholipids in C. euxinus (copepodites V and females) were studied. These relationships allowed to display not only simple trophic relations between isolated parts of the C. euxinus population and phytoplankton, but also selective role of individual algae species in forming lipid reserves too. Besides it was found that geographical variability of chlorophyll concentration and phytoplankton biomass correlates closely only with those lipid fractions (wax esters and phospholipids) of C. euxinus, which accumulated and kept in a body for a fairly long time. No correlation was found between phytoplankton and for rapidly metabolized triacylglycerols, which have to be utilized within few hours.

本野外研究针对桡足类C. euxinus的第五期桡足幼体（copepodites V）与雌性成体，分析了其体内叶绿素浓度、浮游植物生物量（总生物量、个体粒径与物种组成）与总脂质、蜡酯（wax esters）、三酰甘油（triacylglycerols）及磷脂（phospholipids）积累水平之间的关联。该关联不仅揭示了C. euxinus种群离散个体与浮游植物间的基础营养关系，同时也阐明了不同藻类物种在构建该桡足类脂质储备过程中的选择性作用。此外，研究发现叶绿素浓度与浮游植物生物量的地理变异，仅与C. euxinus体内两类可长期留存于体内的脂质组分——蜡酯与磷脂——存在紧密相关性。而针对需在数小时内即被代谢消耗的快速代谢型三酰甘油，则未观测到其与浮游植物相关指标间存在显著关联。