Vertical microalgae fluxes at the mooring station LOMO-2 over the Lomonosov Ridge in the period from September 15, 1995 till August 16, 1996@en

The first studies of microalgae fluxes over the Lomonosov Ridge in the northern Laptev Sea were carried out with a sediment trap at the year-long mooring station LOMO-2, installed at 150 m depth from September 15, 1995 to August 16, 1996. These studies demonstrated essential seasonal variations of vertical microalgae flux. It was shown that in summer diverse flora (composed mainly of cryophylic diatoms) growed intensively beneath the permanent ice cover. Strongly pronounced seasonal variations of microalgae growth correlate closely with solar radiation. Exactly during the maximum insolation period, from the middle of July until the end of September, the microalgae flux was hundreds of times higher than that in the rest of the year. Summer values of the microalgae flux over the Lomonosov Ridge in the northern Laptev Sea were similar to those in the Weddell Sea (Antarctic) and exceeded summer flux values in the Norwegian and Greenland Seas and in the St. Anna Trough (northwestern Kara Sea).本研究首次针对拉普捷夫海北部罗蒙诺索夫海岭（Lomonosov Ridge）的微藻通量（microalgae flux）开展观测，于1995年9月15日至1996年8月16日期间，在水深150米处的锚泊站位（mooring station）LOMO-2部署沉积物捕获器（sediment trap），完成了为期一整年的连续观测。本次观测证实垂直微藻通量存在显著的季节性变化特征。研究表明，夏季时以嗜寒硅藻（cryophylic diatoms）为主要类群的多样微藻群落，在永久冰盖（permanent ice cover）下方呈现出旺盛的生长态势。微藻生长的显著季节性变化与太阳辐射强度密切相关，恰在7月中旬至9月末的日照辐射（insolation）峰值时段，微藻通量较其余时段高出数百倍。拉普捷夫海北部罗蒙诺索夫海岭的夏季微藻通量水平，与南极威德尔海（Weddell Sea）的观测结果相近，且显著高于挪威海（Norwegian Sea）、格陵兰海（Greenland Sea）以及喀拉海（Kara Sea）西北部圣安娜海槽（St. Anna Trough）的夏季通量数值。