Contribution of different algae groups in their total biomass and biomass of Infusoria and Nematoda

In April 2002 at four stations located in the vicinity of the White Sea Biological Station, Zoological Institute, Russian Academy of Sciences (Chupa Inlet, Kandalaksha Bay) ice samples were taken. It was shown that phototrophic and heterotrophic flagellates inhabit White Sea ice together with diatoms and dinoflagellates. In addition to three well-known communities, namely, assemblages of the lower ice surface, assemblages of pore channels, and interstitial communities, an infiltration assemblage and that of melt ice pools not described for the White Sea before were found in the White Sea ice. Biomass of ice algae varied from 130 to 1400 mg C/m**2. Maximum biomass was observed in the lower part of ice (from 2.5 to 36 g C/m**3 or 50-720 mg C within the lower 2-4 cm layer). It is shown that beginning of spring algal growth in the White Sea should be related not to the period of release of the sea from ice and subsequent water warming, but to the period of ice melting at the sea-ice interface and, correspondingly, to increase in its illumination. Sea-ice algae entering water from ice long before beginning of spring ''bloom'' of typical pelagic phytoplankton are grazed by planktonic heterotrophs directly under sea ice and serve at this period as a basis for the pelagic food chain.2002年4月，科研人员于俄罗斯科学院动物研究所白海生物站周边的四个采样站位（楚帕湾、坎达拉克沙湾）采集海冰冰样。研究显示，光合营养型与异养型鞭毛虫与硅藻、甲藻一同栖息于白海海冰生境中。除三类已被充分报道的群落——即冰下表面群落、孔隙通道群落与间隙群落——之外，本次研究还在白海海冰内发现了此前未在该海域被记录的渗透群落与融冰池群落。冰藻的生物量区间为130~1400 mg C/m²，其中冰体下层的生物量最高，可达2.5~36 g C/m³，对应冰体下层2~4 cm范围内的碳含量为50~720 mg。研究表明，白海春季藻类增殖的起始节点并非与海冰消融、海水升温同步，而是与海冰界面处的融冰过程相关，对应光照条件的提升。在典型远洋浮游植物春季“水华”发生的许久之前，海冰藻类便已从冰体释放入海；此时这些海冰藻类会被海冰下方的浮游异养生物摄食，并成为该时期远洋食物链的基础。