Radiocarbon Studies of Dissolved and Particulate Organic Carbon in the Eastern North Pacific and Amazon Plume Regions

在两个开阔洋研究有机碳循环 反映碳衍生物潜在差异的地点 从海洋和陆地来源。 碳的研究 同位素和溶解的和颗粒状的有机碳， 在东北太平洋的“M”站和 大西洋的亚马逊河羽流区。 的 控制DOC浓度。14 C自然值 还将评价微生物组合。 关系 不同的碳库，包括沉积物 有机碳（SOC），将在“M”站进行评估， 高初级生产力和低初级生产力时期， 亚马逊河羽流/大西洋沃茨。 以下问题将得到解决：（1）碳 种及。14 C梯度是季节性碳通量的函数 在开放的海洋中，？ (2)什么是贡献 陆地上的碳物种转移到公海 （三） 同位素放射性是否相对于粒子而分馏 尺寸和/或有机成分？ (4)哪一部分 总DOC池是潜在不稳定和真正难治的， 什么是。每个馏分的14 C签名？

The organic carbon cycle will be studied at two open ocean sites which reflect potential differences in carbon derived from marine and terrestrial sources. Studies of carbon isotopes and dissolved and particulate organic carbon will be conducted at Station "M" in the Northeast Pacific Ocean and in the Amazon River plume region of the Atlantic Ocean. The control of DOC concentrations and . 14C values by natural microbial assemblages will also be evaluated. Relationships between the different carbon pools, including sedimentary organic carbon (SOC), will be assessed at Station "M" during periods of high and low primary productivity and in a transect of Amazon River plume/Atlantic Ocean waters. The following questions will be addressed: (1) Are carbon species and . 14C gradients a function of seasonal carbon flux rates in the open ocean? (2) What is the contribution of terrestrially derived carbon species to the open ocean? (3) Are isotopes activities fractionated with respect to particle size and/or organic composition? (4) What fraction of the total DOC pool is potentially labile and truly refractory, and what are the . 14C signatures of each fraction?