In Situ Rates of Sulfate Reduction and Volatile Organic AcidMetabolism in the Black Sea

该项目的重点是黑海缺氧水柱和表层沉积物中硫酸盐的还原速率。结合沉积物柱中测得的有机碳埋藏率和正在进行的沉积物捕集研究确定的输入速率，结果将提供碳和硫循环速率和深度分布的重要定量信息。对水柱和沉积物中短链有机酸浓度分布以及放射性示踪剂就地周转率的额外测量应能提供有关有机酸，特别是醋酸盐和其他潜在重要中间体的作用的新见解。水柱速率测量将由经过现场测试的采样器孵化装置(SID)进行，该装置能够直接在现场执行样品采购、放射性示踪剂引入、孵化以及亚样品的时间序列提取和固定等所有操作。泥沙速率测量将使用自由落体三脚架运载器进行。这些车辆将配备新开发的泥沙喷射器，使放射性示踪剂能够在连续的轨道上从10厘米深的表面准确地引入到上面的绒毛层中。

This project is focused on sulfate reduction rates in the anoxic water column and superficial sediments of the Black Sea. In combination with measured organic-carbon burial-rates in the sediment column, and input rates determined by ongoing sediment trap studies, the results will provide important quantitative information of rates and depth distributions of both carbon and sulfur cycling. Additional measurements of short-chain organic- acid-concentration distributions plus in situ radiotracer turnover rates in the water column and sediments should provide new insights concerning the roles of organic acids, particularly acetate, and other potentially significant intermediates. Water column rate measurements will be conducted by a field- tested instrument, the Sampler Incubation Device (SID), that is capable of performing all operations of sample procurement, radiotracer introduction, incubation, and time series withdrawal and fixation of subsamples directly in situ. Sediment rate measurements will be conducted using free-fall tripod vehicles. These vehicles will be equipped with newly developed sediment injectors that will permit the accurate in situ introduction of radiotracers in a continuous track from a depth of 10 cm through the surface and into the overlying fluff layer.