Primary productivity and chlorophyll a in Prydz Bay and its mouth in Antarctica during the austral summer of 1999/2000

The investigation of phytoplankton standing stock, euphotic layer and photosynthesis rate were carried out in 19 27 of January, 2000 at three longitudinal sections (70°30′E, 73°00′E and 75°30′E). The results showed that the high value of chlorophyll a concentration was in inshore bay, polynya and the continental slope of the investigated sea area. At various investigated stations, average chlorophyll a concentration at sub surface layer (25 m) was higher than that at surface layer; its concentration at the deeper layers of over 50 m decreased with increasing depth. At anchor station, the maximum chlorophyll a concentration appeared at surface layer in Antarctic summer's afternoon while the minimum value appeared in the morning; chlorophyll a concentration at water layer of 0 25 m was obviously higher than that at deep water layer, being related to the releasing of ice algae. High productivity was in inshore bay and polynya of continental shelf. Chlorophyll a concentration at surface layer is closely correlated to the dissolved oxygen concentration in seawater. The sea area with chlorophyll a concentration of over 1.0 μg/dm 3 may be the convergence of CO 2 and that of below 1.0 μg/dm 3 may be the source of CO 2.

1998/1999年南极夏季普里兹湾及北部海区叶绿素a和初级生产力的分布特征

1998 /1 999年南极夏季 ,作者随“雪龙船”在南极普里兹湾及其北部海区 (63° - 69°1 2′S ,70°30′- 75°30′E) 3条断面 2 4个测站进行浮游生物现存量和初级生产力的现场观测 ,研究叶绿素a浓度和初级生产力的分布特征。测区表层叶绿素a浓度为 0 .1 6 - 3 .99μg/dm3,普里兹湾内和湾西部四女士浅滩海域浓度在 3 .5μg/dm3以上 ;平面分布趋势从湾内向西北方向递减 ,深海区浓度在 0 .5μg/dm3以下。从垂向看叶绿素a浓度的最大值大多出现于 2 5m或 50m层 ,50m以下更深层的浓度随深度的增加而降低 ,2 0 0m层叶绿素a浓度分布范围为 0 .0 1 - 0 .95μg/dm3。粒径分级叶绿素a浓度以微小型浮游生物的贡献占优势 (56 % ) ,微型浮游生物的贡献占2 4 % ,微微型浮游生物的贡献占 2 0 %。测区潜在初级生产力为 0 .1 1～ 1 1 .67mgC/(m3·h) ,平均值为 2 .0 0± 2 .80mgC/(m3·h)。高生产力区位于普里兹湾 ,平均现场生产力达到 0 .86gC/(m2 ·d) ;依次为陆架区、陆坡区 ,深海区生产力较低 ,平均现场生产力为 0 .1 7gC/(m2 ·d)。光合作用同化数较低 (1 .53± 1 .1 1mgC/(mgChla·h) )。粒径分级初级生产力以微小型浮游生物的贡献占优势 (58% ) ,微型浮游生物的贡献占 2 6 % ,微微型浮游生物的贡献占 1 6 %。浮游植?

南极夏季普里兹湾邻近海域浮游植物、粒度分级叶绿素a和初级生产力的分布

１９９１／１９９２年夏季，在南极普里兹湾邻近海域现场观测浮游植物细胞丰度、优势种类组成、颗粒有机碳浓度、粒度分级叶绿素ａ浓度和初级生产力的分布。调查海域现存生物量和初级生产力以及颗粒有机碳浓度分布均具有较明显的时间和空间区域性特征。在普里兹湾邻近北部陆架和测区东部海区现存生物量、初级生产力和颗粒有机碳浓度均较高，西部海区上述生物参数均较低。测区微型和微微型浮游生物代谢生理活性高，能量转换速率快，在现存生物量和生产力中均占较高比重。其对初级生产力的贡献要高于对生物量的贡献。