Benthic O2 and Carbonate Fluxes: Microelectrode Studies

表层土壤有机质降解与碳酸盐溶解 深海沉积物控制着底栖生物流入海水的通量， 有机碳和碳酸钙的保存程度 海洋 使用微电极研究这些过程， 测量电导率、氧气和pH值的梯度 沉积物-水界面 某些pH值结果的模拟研究 到目前为止，方解石溶解的速率是 压力依赖性和速率常数是几个数量级 小于实验室测定值。 最近的田间 微电极氧计算通量与 pH值数据，没有观察到在着陆器通量。 这一结果 与目前对CaCO 3机制的认识不同， 在海底的溶解，正在并将通过探索 可能解释这种差异的机制。 这项研究将 重点关注微电极剖面和着陆器通量的横断面 穿过东部塞阿拉海隆的饱和层 赤道大西洋 这项研究是一项合作实验 Richard Jahnke博士（OCE-9201896）正在进行一项底栖生物 在这一领域的实验。 成岩作用机理及 将通过测量pCO 2检测pH值测定的完整性 通过沉积物-水界面，使用光纤传感器 在过去的一年里建造的。

Organic matter degradation and carbonate dissolution in surficial deep-sea sediments control benthic fluxes to sea water and the extent of organic carbon and calcium carbonate preservation in the ocean. These processes are studied using microelectrodes to measure gradients of conductivity, oxygen and pH across the sediment-water interface. A modelling study of certain pH results to date reveals that the rate the in situ of calcite dissolution is pressure-dependent and the rate constant is several orders of magnitude less than laboratory-determined values. A recent field comparison between fluxes calculated from microelectrode oxygen and pH data, was not observed in the lander fluxes. This result departs from present perceptions about the mechanisms of CaCo3 dissolution on the sea floor, is and will be tested by exploring mechanisms that might explain the discrepancy. The research will focus on a transect of microelectrode profiles and lander fluxes across the saturation horizon on the Ceara Rise in the eastern equatorial Atlantic Ocean. The study is a collaborative experiment with Dr. Richard Jahnke (OCE-9201896) who is carrying out a benthic flux experiment in this area. Diagenesis mechanisms and the integrity of pH determinations will be tested by measuring pCO2 across the sediment-water interface using a fiber-optic sensor constructed during the past year.