Radiocarbon Studies of Dissolved and Particulate Organic Carbon Cycling in the North Pacific and Antarctic Oceans

9501531 BAUER 有机碳库将在两个公海地点进行研究，这反映了极地和温带地区碳循环和转化的潜在差异。 碳同位素特征（14C、13C）以及溶解、胶体和颗粒有机碳（DOC、COC、POC）的浓度将在东北太平洋和印度洋以南的南极洋的 M 站进行测量。 将研究以下碳库：DOC的紫外线和高温催化氧化部分（DOCuv和DOChtc）、悬浮和下沉的POC（POCsusp和POCsink）、悬浮和下沉的POC和COC的COC特定有机成分（总可水解氨基酸THAA、总碳水化合物TCHO、总脂质）、海底碎屑聚集体、海洋雪和溶解的无机碳（DIC）。 将解决以下问题： 1）南极 DOC、POCsusp 和 COC 中的 14C 剖面是否支持深层 DOC 通过世界深海准保守输送的假设？ 2）来自陆架/斜坡的有机质向深海的横向输送如何随时间变化？水体中的POCsusp和POCsink对DOC的吸附程度如何？ 3) COC、POCsink 和 POCsusp 的特定有机成分源自什么深度以及它们如何回收？ 4) 碎屑聚集体和海洋雪的碳来源是什么？在再矿化过程中是否专门利用不稳定的表面衍生化合物？ 5) DOC 在异养利用方面的总体不稳定和难控制性质是什么？微异养生物量的 14C 特征揭示了深海中 DOC/COC/POC 同化的什么？

9501531 BAUER Organic carbon pools will be studied at two open ocean sites that reflect potential differences in carbon cycling and transformations in polar and temperate regions. Carbon isotopic signatures ( 14C, 13C) and concentrations of dissolved, colloidal and particulate organic carbon (DOC,COC,POC) will be measured at Station M in the Northeast Pacific Ocean and in the Antarctic Ocean south of the Indian Ocean. The following carbon pools will be studied: ultra-violet and high-temperature catalytically-oxidizable fractions of DOC (DOCuv and DOChtc), suspended and sinking POC (POCsusp and POCsink), COC specific organic constituents (total hydrolyzable amino acids THAA , total carbohydrates TCHO , total lipids) of suspended and sinking POC and of COC, detrital aggregates on the seafloor, marine snow, and dissolved inorganic carbon (DIC). The following questions will be addressed: 1) Do the 14C profiles in Antarctic DOC, POCsusp, and COC support the hypothesis that deep DOC is transported quasi-conservatively through the world's deep ocean? 2) How does the lateral transport of shelf/slope derived organic matter to the deep sea change with time and what is the extent of adsorption of DOC onto POCsusp and POCsink in the water column? 3) From what depths do specific organic constituents of the COC,POCsink, and POCsusp, originate and how are they recycled? 4) What are the sources of carbon to detrital aggregates and marine snow, and are the labile, surface-derived compounds utilized exclusively during remineralization? 5) What is the overall labile and refractory nature of DOC with respect to its heterotrophic utilization, and what does the 14C signature of microheterotrophic biomass reveal about the assimilation of DOC/COC/POC in the deep ocean?