Collaborative Research: Measuring Ocean Productivity from the Diurnal Change in Oxygen and Carbon

海洋初级生产率是海洋食物网的基础，也是碳从表层沃茨向深海移动的基础，被称为生物泵。然而，人们对初级生产力的空间和时间变化知之甚少，因为目前衡量初级生产力的方法所需的工作量很大，限制了其应用，而且该方法存在难以量化的偏差。使用一种新的方法组合，研究人员将估计三个生态不同地点的海洋每日初级生产力。这项研究将大大提高对初级生产力变化及其对海洋生物泵影响的理解，这将有利于参与碳循环建模的更广泛的海洋社区，并通过海洋初级生产力对大气二氧化碳吸收和未来气候变化的影响造福社会。研究结果将纳入两所院校的本科生和研究生课程以及外联讲座。俄勒冈州州立大学和华盛顿大学的本科生将积极参与该项目。在过去的十年中，一种基于测量溶解氧（O2）气体同位素组成的原位初级生产力方法在海洋学界获得了广泛的关注，因为它可以从简单的水样收集中得出初级生产力的估计。这种方法已经产生了全流域的初级生产力快照的基础上进行采样的表面海洋的机会。然而，需要对初级生产力过程中产生的氧/颗粒有机碳（O2/POC）进行准确估计，以将基于氧的初级生产率转换为碳生产。在这个项目中，每日在三个海洋站点的表层海洋的初级生产率将估计从连续测量的昼夜周期的氧/氩溶解气体比和POC，并比较同时在体外初级生产力估计。将确定初级生产过程中产生的O2/POC的变化。基于O2和POC昼夜周期测量的自主浮子初级生产量估计值将使用船基测量进行验证。根据这项研究产生的自主测量结果对初级生产力进行估计，有可能彻底改变我们对海洋初级生产力时空变化的认识。

The rate of primary production in the ocean is fundamental to the ocean's food web and the movement of carbon from surface waters to the deep ocean, known as the biological pump. Yet spatial and temporal variations in primary productivity are poorly known because the effort required for the current method of measuring primary productivity is significant, limiting its application, and the method has biases that are difficult to quantify. Using a novel combination of approaches, the investigators will estimate daily primary productivity in the ocean at three ecologically distinct sites. The research will significantly improve understanding of primary productivity variations and their impact on the ocean's biological pump, which will benefit the broader ocean community involved in carbon cycle modeling and benefit society via the impact of ocean primary productivity on atmospheric carbon dioxide uptake and future climate change. The research results will be incorporated into both undergraduate and graduate course curricula and outreach talks at the two institutions. There will be active undergraduate student participation in the project at both Oregon State University and the University of Washington.Within the last decade, an in-situ primary productivity method based on measuring the isotopic composition of dissolved oxygen (O2) gas has gained traction within the oceanographic community because it yields a primary production estimate from a simple water sample collection. This method has yielded basin-wide snapshots of primary productivity based on underway sampling of the surface ocean by ships of opportunity. However, accurate estimates of oxygen/particulate organic carbon (O2/POC) produced during primary productivity are needed to convert oxygen-based primary production rates to carbon production. In this project, daily in-situ rates of primary production in the surface ocean at three ocean sites will be estimated from continuous measurements of diurnal cycles in the oxygen/argon dissolved gas ratio and POC and compared to simultaneous in vitro primary productivity estimates. Variations in the O2/POC produced during primary production will be determined. Autonomous float-based estimates of primary production based on measurements of diurnal cycles in O2 and POC will be validated using ship based measurements. Estimates of primary production based on autonomous measurements resulting from this research have the potential to revolutionize our knowledge on the spatial and temporal variations in primary productivity in the ocean.