南极中山站近岸海冰生态学研究 Ⅳ.海冰营养盐浓度的季节变化及其与生物量的关系

对１９９２年４月至１２月间中山站近岸海冰营养盐状况以及与生物量的关系进行了分析。为了能与海水中的营养盐进行对比，对海冰融化样的营养盐数据进行了同期冰下海水表层盐度的校正。结果显示，海冰中多数层次的硝酸盐浓度低于冰下表层海水的浓度，而磷酸盐和硅酸盐浓度则正好相反，亚硝酸盐浓度在观测期间均高于冰下表层海水的浓度。海冰营养盐浓度无明显的变化规律，呈现较大的波动，它可以是冰下表层海水的数分之一直至高出一个数量级，除显著的冰底水华期外并不构成冰藻生长的限制因素。海冰营养盐的分布与叶绿素ａ含量无明显的相关性。

SEASONAL VARIATION OF NUTRIENTS IN THE FIRST YEAR SEA ICE NEAR ZHONGSHAN STATION, EAST ANTARCTICA

The nutrient status in the first year sea ice and its relation to ice algal biomass were studied near Zhongshan Station,East Antarctica from April to December in 1992. In order to compare with those in the underlying water column,the nutrients were normalized to the sea water salinity of the surface layer. The results showed that NO 3 N concentrations were relatively lower in most of ice sections,which was contrary to PO 4 P and SiO 3 Si. The concentrations of NO 2 N in the sea ice were always higher than those of surface water. The nutrients are shown to be not the limit factors for the growth of ice algae,and no obvious rules were observed in the vertical distribution and seasonal variation of nutrients. Except NO 3 N in the bottom layer of ice,the nutrient concentrations were weakly related to chlorophyll a concentrations.