Interactions between Cobalt, Cadmium, and Zinc Biogeochemistry and Phytoplankton Dynamics in the Ross Sea

拟议的工作扩展了跨学科船上计划的范围，以调查调节罗斯海中浮游藻类群分布和生产的环境因素，方法是将钴，镉和锌微量金属分析添加到先前资助的项目中所包含的铁成分中。 额外的微量金属分析将对考察的目标起到很大的补充作用，因为已知海洋浮游植物的碳获取取决于碳酸酐酶，而碳酸酐酶是一种金属酶，可被这三种微量元素中的任何一种激活，对罗斯海区域浮游植物丰度的研究表明，生产力主要由两大浮游植物群体控制：南极棕囊藻和硅藻。硅藻往往占主导地位，在高度分层的沃茨，而棕囊藻是占主导地位的地方观察到更深的混合，这意味着棕囊藻是更有效的低光条件下。 已观察到棕囊藻种群导致快速和早期出口的碳从透光层，导致假设，CO2下降可能会显着减少，如果气候引起的上层海洋分层增加。***

The proposed work extends the scope of an interdisciplinary shipboard program to investigate the environmental factors that regulate the distribution and production of antarctic algal groups in the Ross Sea, by adding cobalt, cadmium, and zinc trace metal analyses to the iron component that had been included in a previously funded project. The additional trace metal analyses will be highly complementary to the cruise objectives because carbon acquisition by marine phytoplankton is known to be dependent on carbonic anhydrase, a metalloenzyme that may be activated by any of these three trace elements.Studies of phytoplankton abundances in the Ross Sea region have shown that productivity is dominated by two major phytoplankton groups: Phaeocystis antarctica and diatoms. Diatoms tend to dominate in highly stratified waters, while Phaeocystis is dominant where deeper mixing is observed, implying that Phaeocystis are more efficient under low light conditions. Phaeocystis populations have been observed to cause rapid and early export of carbon from the photic zone, leading to the hypothesis that CO2 drawdown could decrease significantly if climate-induced upper ocean stratification were to increase. ***