Stable Isotopic Constraints on Benthic Carbonate Dissolution

该项目将测定深海孔隙水中溶解无机碳(DIC)的浓度和碳同位素组成(D13C)，以便直接测量沉积物中有机碳氧化与CaCO3溶解的比率。这些数据将被用来检验底栖生物有机质氧化驱动沉积物中CaCO3溶解的假设，底水相对于方解石是过饱和的。这些研究将在两个单独出资的游轮上进行，重点是底栖碳循环。这一合作努力将使现有孔隙水d13C数据的局限性得以克服；同时，d13C结果将通过提供对海底CaCO3溶解速率和垂直分布的独立估计，为这些研究做出宝贵贡献。

This project will determine the concentration and carbon isotopic composition (d13C) of dissolved inorganic carbon (DIC) in deep-sea pore water, in order to provide a direct measure of the ratio of organic carbon oxidation to CaCO3 dissolution in the sediments. These data will be used to test the hypothesis that benthic organic matter oxidation drives CaCO3 dissolution in sediments overlain by bottom water which is supersaturated with respect to calcite. These study will be carried out in two separately-funded cruises which are focused on the benthic carbon cycle. This collaborative effort will enable limitations in the existing pore water d13C data to be overcome; at the same time, the d13C results will make a valuable contribution to these studies, by providing independent estimates of the rate and vertical distribution of benthic CaCO3 dissolution.