234Th/238U disequilibrium and particulate organic carbon export in the northwestern South China Sea

被引：0
作者：
Hao Ma
Zhi Zeng
Wen Yu
Jianhua He
Liqi Chen
Jianping Cheng
Mingduan Yin
Shi Zeng
机构：
[1] Tsinghua University,Department of Engineering Physics
[2] State Oceanic Administration,Key Laboratory of Global Change and Marine
[3] Ministry of Education,Atmospheric Chemistry
[4] Key Laboratory of High Energy Radiation Imaging Fundamental Science for National Defense,Key Laboratory of Particle & Radiation Imaging (Tsinghua University)
来源：
Acta Oceanologica Sinica | 2011年 / 30卷
关键词：
Th-; U disequilibrium; POC export; South China Sea (SCS);
D O I：
暂无
中图分类号：
学科分类号：
摘要：
234Th was utilized as a tracer of particulate organic carbon (POC) export in the northwestern South China Sea (SCS) on the basis of the data collected at four stations during a spring cruise. Depth profiles of dissolved and particulate 234Th activities were measured in the upper 60 m, showing a significant deficit relative to 238U over the investigated stations. A stratified structure of 234Th-238U disequilibrium was in general observed in the upper 60 m water column, indicating that the euphotic zone of the northwestern SCS in this reason can be divided into two layers, an upper and lower layer, with different export rates. POC export fluxes were estimated from a one-dimensional steady state model of 234Th fluxes in combination with the measurement of POC/234Th ratios on suspended particles. The POC export in this region ranged from 8.2 to 20.0 mmol/(m2·d), with an average of 16.0 mmol/(m2·d), and was slightly higher than those previously reported in the southern SCS.
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页码：55 / 62
页数：7
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