Organic Geochemical Studies in the Southern Ocean

南大洋有机地球化学研究

• 批准号: 9531759
• 负责人: Stuart Wakeham
• 金额: --
• 依托单位: Skidaway Institute of Oceanography
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-08-15 至 2000-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9531759&HistoricalAwards=false
• 关键词: Organic; Geochemical; Studies; Southern; Ocean

9531759 Wakeham This research project is part of the US Joint Global Ocean Flux Study (JGOFS) Southern Ocean Program aimed at (1) a better understanding of the fluxes of carbon, both organic and inorganic, in the Southern Ocean, (2) identifying the physical, ecological and biogeochemical factors and processes which regulate the magnitude and variability of these fluxes, and (3) placing these fluxes into the context of the contemporary global carbon cycle. This work is one of forty-four projects that are collaborating in the Southern Ocean Experiment, a three-year effort south of the Antarctic Polar Frontal Zone to track the flow of carbon through its organic and inorganic pathways from the air-ocean interface through the entire water column into the bottom sediment. The experiment will make use of the RVIB Nathaniel B. Palmer and the R/V Thompson. This component concerns a cooperative study of organic matter cycling in the water column and in the surficial sediments of the Southern Ocean. The main goals of the effort are: (1) to determine how the composition and fluxes of organic material vary regionally and seasonally within the Southern Ocean, (2) to relate these variations to biological processing of the punctuated organic input and its siliceous matrix, (3) to follow the downward diagenetic fate of planktonic remains through the water column and into the underlying sediments, with special emphasis on biochemical trends reflecting substrate quality (freshness), and (4) to holistically account for total organic matter at all stages of degradation by carbon-13 analysis of bulk trap and sediment samples. The shipboard work involves collecting suspended and raining particulate material within the water column and from the underlying sediment at several sites along the proposed study transect. Suspended particles will be collected both by plankton net tows and high volume filtration of surface water. Sinking particles will be collected with modular sediment traps deployed in arrays of four. Individual traps will be designed to selectively collect sinking particles and reject swimming zooplankton without loss of sample or biocide. Two of the four traps on each array will be fitted with 12-tube subsampling carousels to study shorter term variations. The collected trap and sediment core samples will be analyzed for their basic biochemical building blocks, such as carbohydrates, amino acids, lipids, lignins, and pigments. These make up the bulk of the organic matter produced in the upper water column and are an important fraction of the material buried in the sediment. At the molecular level they can provide unequivocal information on the sources of organic matter and its decomposition at depth, and on the pathways by which biogenic material is transferred to the sediment. These data will be combined with information obtained during prior JGOFS experiments to produce a global picture of the organic chemistry of particulate matter in the ocean. ***

9531759 Wakeham这项研究项目是美国联合全球海洋通量研究（JGOFS）南方海洋计划的一部分，目的是（1）在南方海洋中更好地理解有机和无机碳的通量，（2）确定这些调节这些幅度和可变性的物理，生态和生态学因素和过程，以这些范围的范围，并将其定位在这些范围内，并将其定位为3.3）全球碳循环。这项工作是在南大洋实验中合作的四十四个项目之一，在南方海洋实验中，在南极极地额叶区以南的三年努力，可以通过其从空气界面通过整个水柱进入底部沉积物的有机和无机途径来跟踪碳的流动。该实验将利用RVIB Nathaniel B. Palmer和R/V Thompson。该组成部分涉及一项关于水柱中有机物循环以及南大洋露面沉积物中的合作研究。努力的主要目标是：（1）确定有机材料的成分和磁通在南部海洋内的区域和季节性变化，（2）将这些变化与穿点性有机输入的生物学处理及其硅质矩阵（3）相关联，以遵循浮游生物的趋势，以供水台上的趋势，以供板柱的下降趋势，以供您的趋势范围内介绍。底物质量（新鲜度）和（4）通过碳-13分析散装陷阱和沉积物样品的分析在所有降解阶段的总体有机物总体上说明了总体有机物。船上的工作涉及在水柱内收集悬浮和降雨的颗粒物，并从沿拟议的研究样带的几个地点的底层沉积物中收集悬浮和下雨的颗粒物。悬浮的颗粒将通过浮游生物净滚水和地表水的大容量过滤收集。下沉的颗粒将使用在四个阵列中部署的模块化沉积物陷阱收集。单个陷阱将设计为选择性地收集下沉颗粒并拒绝游泳浮游动物，而不会丢失样品或杀害剂。每个阵列上的四个陷阱中的两个将配备12块尺的采样旋转木制，以研究较短的期限变化。将分析收集的陷阱和沉积物核心样品的基本生化构建块，例如碳水化合物，氨基酸，脂质，木质素和颜料。这些构成了上水柱中产生的大部分有机物，是埋在沉积物中的材料的重要部分。在分子水平上，他们可以提供有关有机物来源及其深度分解的明确信息，以及将生物材料转移到沉积物的途径上。这些数据将与先前的JGOF实验中获得的信息相结合，以产生海洋中颗粒物质的有机化学的全局图片。 ***