1999年7月白令海海盆营养盐和溶解氧的垂直特征

1999年 7月下旬 ,雪龙号科学考察船在中国首次北极科学考察航次中在白令海海盆北部与中部完成了 2 2个深水站的采样作业。营养盐和溶解氧采样分 1 2层 ,共获得 2 71个样品。分析结果表明 :硅酸盐浓度 Si]、磷酸盐浓度 P]和无机氮浓度 N](硝酸盐 NO3- ]加亚硝酸盐NO2 - ]加氨 NH4 + ],主要成分为 NO3 - ])垂直结构的相似之处在于 :在≤ 2 5m是第一层 ;随后为一个明显的跃层 ;第二层位于 5 0— 2 0 0m之间 ;然后有一个宽的跃层 ;从 5 0 0m至底部 (约3 90 0m)为第三层。其差别在于 :在第三层中 ,Si]继续缓慢增加 ,而 N]和 P]略有减少。溶解氧O2 ]与 Si]、P]、N]的垂直分布表明在潜温 (θ)极小层以上 (0 .5— 2 .7°C ,盐度 3 3 .0 1— 3 3 .1 7,深度 81— 1 5 7m)的海水是海气充分交换层与生物主要活动层。在≥ 1 5 0m以下 ,P]、NO3 - ]两者和 O2 ]有 >0 .9的正相关性。从表层至底部 ,在整个盐度范围内 ,NO]∶PO](其中 NO]=9NO3 - ]+O2 ],PO]=1 3 5 P]+O2 ])在 0 .786 - 1 .0 2 9之间大致均匀分布 ;这表明白令海海盆北部与中部海水的营养特性具有较强的保守性。

VERTICAL FEATURES OF NUTRIENT AND DISSOLVED OXYGEN OF THE BERING BASIN IN JULY 1999

From July 20 to 30,1999, China R/V Xuelong occupied 22 stations in the Bering Basin on the cruise of China First Arctic Science Expedition. The chemical samplings are sum of 271. For vertical distributions of silicate , phosphate , and dissolved inorganic nitrogen (nitrate plus ammonium plus nitrite), the similar point is that there are three layers with two nutriclines. The first layer is in 25m; the followings are obvious nutriclines; the second layer is between 50m and 200m; then there are plain nutriclines; and the third layer is from 500m to bottom (~3900 m). The difference is in the third layer, where slowly increases with depth, but and slowly decrease or remain the same with depth. Vertical oxygen and and and profiles indicate the sea waters within the potential temperature (θ) minimum layer (0.5-2.7°C, salinity of 33.01-33.17,depth of 81-157 m) are active layer of atmospheric oceanic exchange and main layer of biological action. The decreases relate with both and increase in ≥150 m. The : ratios (=9+ and =135+) of the sea waters of the Bering Basin are uniformly 0.786-1.029, indicating that nutrient features of the northern and central Bering Basin seawaters are rather conservative.