Benthic Metabolism in Continental Margin Sediments: Controls on Reaction Rate and Potential Consequences

大陆边缘沉积物中的底栖代谢：反应速率和潜在后果的控制

• 批准号: 9416626
• 负责人: Allan Devol
• 金额: $ 58.2万
• 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: 1995
• 资助国家: 美国
• 起止时间: 1995-06-15 至 2000-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9416626&HistoricalAwards=false
• 关键词: Benthic; Metabolism; Continental; Margin; Sediments

9416626 Devol In this project, the investigator will address one of the major questions on the global carbon cycle: What determines the extent to which organic carbon produced by primary production in the world ocean survives mineralization and is buried in seafloor sediments? The project will continue the investigator's past work in two regions of the western Pacific margin, one off the U.S. Pacific Northwest, the other off the coast of northwestern Mexico. It has commonly been assumed that the amount of particulate organic matter near the sediment-water interface determines the rate of organic mineralization, or oxidation; the process is mediated by heterotrophic bacteria that use either dissolved oxygen or nitrate as oxidant. However, in this study the investigator will also explore the possibly that, when water column oxygen concentrations are low, the concentrations of dissolved oxygen and nitrate (rather than organic matter) may actually control mineralization rates. To clarify these issues, the project will involve field measurements of the rates of organic sedimentation, chemical reactions in the sediments, and (by direct measurement) solute fluxes across the sediment-water interface.

在这个项目中，研究者将解决一个关于全球碳循环的主要问题：是什么决定了世界海洋初级生产产生的有机碳在多大程度上能幸存下来，并被埋在海底沉积物中？该项目将继续研究者过去在西太平洋边缘的两个地区的工作，一个在美国太平洋西北部，另一个在墨西哥西北部海岸。人们通常认为，沉积物-水界面附近的颗粒有机质的数量决定了有机矿化或氧化的速率；这个过程是由异养细菌介导的，它们使用溶解氧或硝酸盐作为氧化剂。然而，在本研究中，研究者还将探索当水柱氧浓度较低时，溶解氧和硝酸盐（而不是有机物）的浓度实际上可能控制矿化率的可能性。为了澄清这些问题，该项目将包括实地测量有机沉积速率、沉积物中的化学反应以及（通过直接测量）沉积物-水界面上的溶质通量。