SGER: Elemental Ratio Anomalies Associated with Antarctic Marine Phytoplankton

摘要-0108759 P.I.最近在JGOFS和ROAVERRS计划下对罗斯海的巡航记录表明，溶解碳和营养物的去除可能与海水颗粒物的典型Redfield比率（例如C：N：P为106：16：1）预测的比率有很大差异。 非Redfield营养盐去除率与浮游植物种类组成。 例如，从溶解无机碳、硝酸盐和磷酸盐的测量确定的C：N：P吸收比为约1.5。80：10：1，在占主导地位的车站和CA。140：20：1为棕囊藻占主导地位的站。 非Redfield动力学对于理解地质记录的地球化学以及预测气候变化的影响至关重要。 将在前往南大洋印度洋部分的海洋物理学巡航（NBP 01-01，霍巴特至开普敦）期间从一艘机遇号船上采集样本。 将通过显微镜对保存的水样中的物种组成进行定量。 营养物浓度（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品中测量，这是一个用于研究碳动力学的取样程序。 这些“机会样本”将提供一套数据，用于评估在罗斯海观测到的非雷德菲尔德情况是否发生在南极洲周围遥远的沿海系统，以及是否与同一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.