SGER: Collaborative Research - Mechanisms behind non-Redfieldian P Cycling in Water Masses of the Southern Ocean, New Insights from X-ray Spectromicroscopy and Electrodialysis

在全球大部分海洋中，氮(N)和磷(N)的(Redfield)比率非常稳定，无论是在海水中这些营养物质的浓度上，还是在它所支持的浮游生物物种中。许多对亚南极模式水的研究表明，与低纬度水域相比，高纬度磷循环改变了红场平衡，导致磷异常丰富。亚南极模式水是一种对流形成的下降水类型，可以通过其异常均匀的性质来识别。基于同步加速器的X射线光谱显微镜将被用来在亚微米尺度上对生物体和海洋颗粒中几种磷形态(如聚磷酸盐、有机磷化合物)的丰度进行化学表征和空间测绘。这些样本将沿着I/B Oden的邮轮轨道进行，从Punta Arenas到McMurdo站，经过Bellinghausen，Amundsen和Ross海地区，将提供来自偏远和未被研究的冰架和冰下生态系统的独特数据集。南极海洋磷状况的特征预计将进一步阐明南大洋磷生物地球化学的各个方面。除了使用可能导致对南大洋P化学方面的变革性重述的新的表征技术外，该项目还符合另一项SGER标准，即代表对瑞典I/B Oden号破冰船从蓬塔阿雷纳斯到麦克默多通过别林豪森、阿蒙森和罗斯海的横断面所提供的国际实地行动机会的快速反应。

In much of the global ocean the (Redfield) ratio of nitrogen (N) to P is remarkably constant, both in the concentrations of these nutrients in seawater and in the plankton species that it supports. A number of studies of sub-Antarctic mode water, a convectively formed descending water type identifiably by its exceptionally uniform properties, suggest that high latitude P cycling is altered from the Redfield balance resulting in unusually enriched P compared to low latitude waters . Synchrotron based x-ray spectromicroscopy will be used to chemically characterize and spatially map, at sub micron dimensions, the abundance of several P forms (e.g. polyphosphates, organo-P compounds) in organisms and marine particulates. These samples will be taken along the cruise track of the I/B Oden as it transits from Punta Arenas to McMurdo Station, through the Bellingshausen, Amundsen and Ross Sea regions,and which will provide a unique data set from a remote and understudied ice shelf and under-ice ecosystem. Characterization of Antarctic ocean P status is expected to shed further light upon aspects of Southern Ocean P biogeochemistry. As well as using novel characterization techniques, which may lead to a transformative restatement of aspects of Southern Ocean P chemistry, this project meets an additional SGER criteria of representing a quick response to an international field campaign opportunity afforded by the transect of the Swedish ice breaker I/B Oden from Punta Arenas to McMurdo through the Bellingshausen, Amundsen and Ross Seas.