Extracellular Carbon and Sulfur Production by Arctic Phytoplankton during the Spring Bloom

这项研究建议评估替代途径在北极浮游植物碳和硫收支中的重要性，并确定营养限制和温度是否控制碳和硫收支中不同有机库的大小以及这些不同矿物库的生产率。浮游植物可以作为二氧化碳的汇，也可以作为二甲基硫化物的来源。大型浮游植物生物量在春季水华期间在北极水域积累，那里硅藻和其他藻类等藻类占主导地位。PI之前的工作表明，极地浮游植物可能比之前认为的更能产生溶解的有机碳和硫。这些物种在北极海高生产力水域的广泛分布使理解这一系统的可变性变得非常重要。PIs建议区分藻胶和溶解碳库的产生，并确定它们在光合作用固定碳总排泄中的相对重要性，确定棕囊藻和硅藻在碳和硫途径中的作用，检查指数生长和平稳生长期间碳和硫分配的变化，并研究营养限制对有机碳和硫产生的作用。

This study proposes to assess the importance of alternative pathways in the carbon and sulfur budgets of Arctic phytoplankton and to determine whether nutrient limitation and temperature control the size of the different organic pools of the carbon and sulfur budgets as well as the production rate of these different mineral pools. Phytoplankton may act as a sink for carbon dioxide and act as a source of dimethylsulfide. Large phytoplankton biomass accumulates during spring blooms in Arctic waters, where algal taxa such as diatoms and other algae dominate. Previous work by the PIs indicated that polar phytoplankton can be strong producers of dissolved organic carbon and sulfur than previously thought. The widespread distribution of these species in highly productive waters of the polar seas makes understanding the variability of this system highly critical. The PIs propose to differentiate between the production of algal mucilage and dissolved carbon pools and determine their relative importance to the total excretion of photosynthetic fixed carbon, to determine the role of Phaeocystis and diatomaceous algae in carbon and sulfur pathways, to examine the changes in partitioning of carbon and sulfur during exponential and stationary growth, and to study the role of nutrient limitation on organic carbon and sulfur production.