234Th as a Tracer of Particulate C and N Export in the Equatorial Pacific

该项目的目标是使用234 Th数据来量化 真光层底部有机碳和氮的颗粒通量 赤道太平洋地区。 234 Th：238 U的测量 1992年春季和秋季的不平衡将被用来 量化南北样带中颗粒234 Th通量 在西经170度到西经110度之间穿过赤道。 的 通量数据将与有机C/234 Th的测量相结合， N/234 Th比率对粒度分级颗粒物， 计算有机碳和氮的颗粒通量。 以 船载γ能谱分析234 Th的优点， 通量数据将接近于真实的时间。 使用一个- 现场泵送系统，所有样品将独立收集， 其他抽样活动。 有了这个数据集， 太平洋在全球碳预算中的作用， 海洋内部的相关营养物质（新生产）将 能够量化。 此外，季节和空间 覆盖范围将允许新生产正在进行的程度 导出为DOM，而不是沉降待解析的粒子，以及 负责确定C效率的过程 将更好地了解上层海洋的出口与回收。

The goal of this project is to use 234Th data to quantify the particulate flux of organic C and N at the base of the euphotic zone in the equatorial Pacific. Measurements of 234Th: 238U disequilibria in the spring and fall of 1992 will be used to quantify the particulate 234Th flux in north to south transects across the equator between 170 degrees W to 110 degrees W. The flux data will be combined with measurements of organic C/234Th and N/234Th ratios on size-fractionated particulate matter, to calculate the particulate flux of organic C and N. By taking advantage of shipboard gamma spectrometric analyses of 234Th, the flux data will be available in close-to-real time. Using an in- situ pumping system, all samples will be collected independent of other sampling activities. With this data set the equatorial Pacific's role in the global C budget for the removal of C and associated nutrients to the ocean's interior (new production) will be able to be quantified. In addition, the seasonal and spatial coverage will allow the extent to which new production is being exported as DOM rather than settling particles to be resolved, and the processes responsible for determining the efficiency of C export vs. recycling in the upper oceans will be better understood.