Sedimentary Pore Water DOC:Fluxes and Molecular Composition

沉积孔隙水 DOC：通量和分子组成

• 批准号: 9618265
• 负责人: Allan Devol
• 金额: $ 45.13万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-03-01 至 2002-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9618265&HistoricalAwards=false
• 关键词: Sedimentary; Pore; Water; DOC; Fluxes

The flux of pore water DOC to overlying waters and the cycling of DOC within sediments are important but poorly constrained components of the oceanic carbon cycle. Preliminary pore water work and in situ benthic tripod flux estimates suggest three hypotheses: 1) marine sediments are an important source of water column DOC, 2) a component of the flux contributes to the refractory water column DOC pool, and 3) A component of the flux may be oxidized near the sediment water interface. The first hypothesis will be tested by using a benthic tripod to accurately measure this flux along a depth gradient reaching across the shelf to upper slope. The second hypothesis will be tested by pooling the overlying water in the flux tripod at the end of several deployments to form an ultrafiltered large volume sample that we will characterize at the molecular level and compare to similarly characterized water column DOC. An in situ dialysis sampler to sample for pore water DOC concentration and in situ oxygen concentration manipulation experiments will test the third and all will take place along the Pacific Northwest cost, off the northwest coast of Mexico and in the Puget Sound.

孔隙水DOC对上覆水体的通量和沉积物中DOC的循环是海洋碳循环的重要组成部分，但约束较差。初步的孔隙水工作和原位底栖三脚架通量估计提出了三个假设：1)海洋沉积物是水柱DOC的重要来源；2)通量的一部分有助于形成耐火水柱DOC池；3)通量的一部分可能在沉积物水界面附近被氧化。第一个假设将通过使用底栖三脚架来精确测量沿深度梯度到达上斜坡的通量来验证。第二个假设将通过在几次部署结束时将通量三脚架上的水汇集在一起来测试，形成一个超滤的大体积样品，我们将在分子水平上对其进行表征，并将其与具有类似特征的水柱DOC进行比较。第三个测试将采用原位透析采样器对孔隙水中DOC浓度进行采样，并进行原位氧浓度操纵实验，所有这些都将沿着太平洋西北海岸、墨西哥西北海岸和普吉特海湾进行。