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利用14C吸收法、3H吸收法、234Th/238U不平衡法和210Pbex测年法分别测定了北冰洋的初级生产力、细菌生产力、颗粒有机碳输出通量及沉积物有机碳埋藏速率.结果表明,北冰洋水柱积分生产力介于3.8～197.1mmolC/m2·d,高于早期的报道值,其中楚克奇陆架区初级生产力水平高于深海盆地.积分细菌生产力与初级生产力的比值大于0.5,表明在北冰洋寒冷的水体中细菌活动并未受到明显限制.由234Th/238U不平衡获得的234Th亏损程度、溶解态与颗粒态234Th停留时间、颗粒有机碳的输出通量均证实,北冰洋深海盆地仍存在一定的颗粒清除、迁出作用.夏季期间楚克奇陆架沉积物有机碳埋藏速率为25～35 mmol C/m2·d,占水柱初级生产力的 59％～82％,表明有机碳的输送与埋藏是非常高效的.上述证据均表明,至少在夏季期间,北冰洋并非生物生产力极其贫瘠的海洋“沙漠”,它存在相对活跃的海洋碳循环过程,重新评估北冰洋在全球碳循环中的作用显得更为重要.
The primary productivity, bacterial productivity, particulate organic carbon output flux and burial rate of organic carbon in the Arctic Ocean were measured by 14C absorption, 3H absorption, 234Th / 238U imbalance and 210Pbex dating respectively.The results show that the Arctic Ocean water column The integral productivity ranged from 3.8 to 197.1 mmolC / m2 · d, which was higher than the earlier reported value, of which the primary productivity in the Chuchqi shelf area was higher than that in the deep-sea basin.The integral bacteria productivity to primary productivity ratio was greater than 0.5, indicating that in the Arctic cold The bacterial activity in the water body was not obviously restricted.The level of 234Th loss, the dissolved state and the 234Th residence time of particulate state and the output flux of particulate organic carbon were confirmed by the 234Th / 238U imbalance, and some particle removal still exists in the Arctic deep-sea basin During the summer, organic carbon burial rate of 25 ~ 35 mmol C / m 2 · d, accounting for 59% -82% of the primary productivity of water column, indicating that organic carbon transportation and burial are very efficient All of the evidence above shows that, at least during the summer months, the Arctic Ocean is not a very barren ocean “desert” of biological productivity and it is relatively active Ocean carbon cycle, re-evaluate the role of the Arctic in the global carbon cycle is more important.