Dissolved Organic Phosphorus Cycling in the Coastal Ocean

伍兹霍尔海洋研究所的一名研究人员将参加由海岸海洋过程(COOP)计划资助的海岸海洋陆架运输进展(COOP)项目的巡航和现场实验。参与这项研究的PI将为项目增加一个磷成分，从而使俄勒冈州近海海岸系统中碳、氮和磷循环的耦合动力学得到解决。利用海岸采样计划提供的高时空分辨率，PI计划开展以下研究：(1)确定溶解有机磷(DOP)和颗粒有机磷(POP)的三维分布，以及它们与溶解有机碳(DOC)、颗粒有机碳(DON)、颗粒有机氮(DON)和其他生物参数分布的关系；(2)确定溶解有机碳和颗粒有机磷的C：N：P比值的动态变化；(3)评估耦合DOC、DON、DOP的短期(在每21天航次的样带重采样期间)与季节变化；以及(4)评估地形对DOP、POP循环和跨陆架输送的影响。此外，DOP的生物利用度将通过监测田间样品中DOP的酶水解程度来评估。现场浮游植物与磷胁迫的营养状态将通过散装和细胞特异性酶标记的荧光(ELF)碱性磷酸酶(APase)来确定，而浮游植物对诱导或缓解磷限制的物种特异性反应将使用ELF-APase在船上营养物质修正孵化中进行评估。

ABSTRACTOCE-0119134A researcher from Woods Hole Oceanographic Institution will participate in the cruises and field experiments of the Coastal Ocean Advances in Shelf Transport (COAST) project funded by the Coastal Oceans Processes (CoOP) program. The participation of this PI in the study will add a phosphorus component to the project thereby allowing the coupled dynamics of carbon, nitrogen and phosphorus cycling in the coastal system off Oregon to be resolved. Taking advantage of the high temporal and spatial resolution provided by the COAST sampling plan, the PI plans to carry out the following research: (1) determine the 3-dimensional distributions of dissolved organic phosphorus (DOP) and particulate organic phosphorus (POP), and how they relate to distributions of dissolved organic carbon (DOC), particulate organic carbon, dissolved organic nitrogen (DON), particulate organic nitrogen and other biological parameters; (2) ascertain the dynamic variability of the C:N:P ratios of the dissolved and particulate organic pools; (3) assess the short term (during transect re-sampling on each 21-day cruise) versus seasonal variations in coupled DOC, DON, DOP; and (4) evaluate the effects that topography has on DOP and POP cycling and cross-shelf transport. In addition, DOP bioavailability will be evaluated by monitoring the extent of enzymatic DOP hydrolysis in field samples. The nutritional status of in-situ phytoplankton with regard to phosphate stress will be determined by bulk and cell-specific Enzyme Labeled Fluorescence (ELF) Alkaline phosphatase (APase) and the species-specific response of phytoplankton to induced or alleviated P-limitation will be assessed using ELF-APase in shipboard nutrient amendment incubations.