利用2011年南极夏季在普里兹湾获取的海水样,分析测定了叶绿素a、磷酸盐、硅酸盐、硝酸盐和铵盐的含量.结果表明,普里兹湾表层海水中时间/min的含量普遍具有冰架边缘＞陆架区＞陆坡及深海区的分布特征,海冰的消融及水体的稳定性是影响表层海水Chla分布的主要原因.Chla含量的垂直分布与光照条件相关,基本上都具有上层水体含量高,随着深度逐渐降低的分布特征.磷酸盐、硅酸盐和硝酸盐的水平及垂直分布特征都与Chl a的分布格局相反.表层海水中铵盐的分布特征与磷酸盐等主要营养盐的分布格局相反,冰架边缘、陆架区铵盐的垂直分布特征与陆坡及深海区不同,在冰架边缘和陆架区有机质降解过程主导着水柱中铵盐的浓度,而浮游植物吸收作用与有机质降解过程之日的平衡控制着陆坡及深海区铵盐的垂直分布.根据Chlα与营养盐的浓度及分布特征,结合温度、盐度、溶解氧饱和度等水文要素,分析探讨了Chlα深层最大值现象(DCM)的成因及67.5°S以南表层海水中铵盐对硝酸盐吸收的抑制作用.%Water samples from Prydz Bay were collected during the Antarctic summer of 2011 and the contents of chlorophyll a ( Chl a) and other nutrients were analyzed. The results showed that the concentration of Chl a in the surface water of Prydz Bay was highest at the margin of the ice shelf, lower at the continental shelf and lower again at the continental slope and in the open sea. The melting of ice and the stability of the water body were the main factors influencing Chl a distribution in the surface water. The vertical distribution of Chl a was related to irradiation, the upper water had a high content and it decreased with depth. The horizontal and vertical distribution of phosphate, silicate and nitrate was opposite to that of Chl a. The distribution of ammonium in the surface water was opposite to that of the other main nutrients and the vertical distribution of ammonium at the margin of the ice shelf and at the continental shelf differed compared with the distribution at the continental slope and in the open sea. The degradation of organic matter primarily controlled the ammonium content in the water column at the margin of the ice shelf and at the continental shelf, however the balance between uptake by phytoplankton and the degradation of organic matter controlled the ammonium content at the continental slope and in the open sea. According to the content and distribution of Chl a and other nutrients, the characteristics of the deep chlorophyll maximum (DCM) and the impact of the inhibition of ammonium on nitrate uptake in the surface water south of 67. 5°S were discussed.
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