SGER: Elemental Ratio Anomalies Associated with Antarctic Marine Phytoplankton

abstractopp - 0108759 - p。最近在JGOFS和ROAVERRS计划下的罗斯海巡航记录了溶解碳和营养物质的去除可能与典型的Redfield比率（例如碳：氮：磷106:16:1）预测的海水颗粒的比例有很大不同。非redfield营养物去除率与浮游植物种类组成有关。例如，通过测量溶解的无机碳、硝酸盐和磷酸盐确定的碳：氮：磷吸收比在硅藻为主的站中约为80:10:1，在南极褐囊藻为主的站中约为140:20:1。非雷德菲尔德动力学对于理解地质记录的生物地球化学以及预测气候变化的影响至关重要。样本将在前往南大洋印度洋区域的地球物理巡航（NBP 01-01，霍巴特至开普敦）期间从机遇号船上收集。物种组成将通过显微镜从保存的水样中定量。营养物质浓度（硝酸盐、亚硝酸盐、磷酸盐和硅酸盐）将从与水一起收集的冷冻样本中进行测量，这是一项用于研究碳动力学的采样计划。这些“机会样本”将提供一组数据，用于评估在罗斯海观察到的非雷德菲尔德情况是否发生在南极洲周围的遥远沿海系统中，以及它是否与相同的物种或类似的海洋条件有关。

AbstractOPP-0108759P.I. Michael LizotteRecent cruises to the Ross Sea under the JGOFS and ROAVERRS programs have documented that the removal of dissolved carbon and nutrients can be significantly different from the ratios predicted from typical Redfield ratios (e.g. 106:16:1 for C:N:P) for seawater particulates. The non-Redfield nutrient removal ratios were associated with phytoplankton species composition. For example, C:N:P uptake ratios determined from measurements of dissolved inorganic carbon, nitrate and phosphate were ca. 80:10:1 in diatom-dominated stations and ca. 140:20:1 for Phaeocystis antarctica-dominated stations. Non-Redfield dynamics could be critical for understanding the biogeochemistry of the geological record as well as predicting the impacts of climate change. Samples are to be collected from a ship of opportunity during a geophysics cruise (NBP 01-01, Hobart to Capetown) to the Indian Ocean sector of the Southern Ocean. Species composition will be quantified by microscopy from preserved water samples. Nutrient concentrations (nitrate, nitrite, phosphate, and silicate) will be measured from frozen sampled collected in conjunction with water a sampling program that is to be conducted to study carbon dynamics. These "samples of opportunity" will provide a data set to be used in evaluating whether the non-Redfield situation observed in the Ross Sea occurs in distant coastal systems around Antarctica, and whether it is associated with the same species or similar oceanographic conditions.