Dissolved Organic Phosphorus Cycling in the Coastal Ocean

来自伍兹霍尔海洋研究所的研究员将参加海岸海洋过程（CoOP）计划资助的海岸海洋大陆架运输进展（COAST）项目的巡航和实地实验。该项目负责人的参与将为该项目增加磷成分，从而使俄勒冈州沿海系统中碳、氮和磷循环的耦合动力学得以解决。利用COAST采样方案提供的高时空分辨率，PI计划开展以下研究：(1)确定溶解性有机磷（DOP）和颗粒性有机磷（POP）的三维分布，以及它们与溶解性有机碳（DOC）、颗粒性有机碳、溶解性有机氮（DON）、颗粒性有机氮等生物参数分布的关系；(2)确定溶态有机池和颗粒有机池C:N:P比值的动态变化；(3)评估短期（在每21天巡航的样带重新采样期间）耦合DOC、DON、DOP的季节性变化；(4)评价地形对DOP和POP循环和跨大陆架运输的影响。此外，将通过监测田间样品中酶解DOP的程度来评估DOP的生物利用度。原位浮游植物在磷酸盐胁迫下的营养状况将通过体积和细胞特异性酶标记荧光（ELF）碱性磷酸酶（APase）来确定，并将在船上的营养修正孵育中使用ELF-APase来评估浮游植物对诱导或减轻磷限制的物种特异性反应。

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.