Marine Radionuclide Research Center, Korea Institute of Ocean Science and Technology, Ansan 15627, South Korea.
Department of Oceanography, Pusan National University, Busan 46241, South Korea.
Sci Total Environ. 2017 Apr 15;584-585:154-163. doi: 10.1016/j.scitotenv.2017.01.165. Epub 2017 Jan 29.
We investigated horizontal and vertical distributions of DMS in the upper water column of the Amundsen Sea Polynya and Pine Island Polynya during the austral summer (January-February) of 2016 using a membrane inlet mass spectrometer (MIMS) onboard the Korean icebreaker R/V Araon. The surface water concentrations of DMS varied from <1 to 400nM. The highest DMS (up to 300nM) were observed in sea ice-polynya transition zones and near the Getz ice shelf, where both the first local ice melting and high plankton productivity were observed. In other regions, high DMS concentration was generally accompanied by higher chlorophyll and ΔO/Ar. The large spatial variability of DMS and primary productivity in the surface water of the Amundsen Sea seems to be attributed to melting conditions of sea ice, relative dominance of Phaeocystis Antarctica as a DMS producer, and timing differences between bloom and subsequent DMS productions. The depth profiles of DMS and ΔO/Ar were consistent with the horizontal surface data, showing noticeable spatial variability. However, despite the large spatial variability, in contrast to the previous results from 2009, DMS concentrations and ΔO/Ar in the surface water were indistinct between the two major domains: the sea ice zone and polynya region. The discrepancy may be associated with inter-annual variations of phytoplankton assemblages superimposed on differences in sea-ice conditions, blooming period, and spatial coverage along the vast surface area of the Amundsen Sea.
我们使用搭载在韩国破冰船“Araon”号上的膜进样质谱仪（MIMS），于 2016 年南极夏（1-2 月）期间调查了南极洲阿蒙森海冰间湖和松岛冰间湖上层水体中 DMS 的水平和垂直分布。表层水中 DMS 的浓度从<1 到 400nM 不等。在海冰-冰间湖过渡区和 Getz 冰架附近，DMS 浓度最高（高达 300nM），这两个地方都出现了第一次当地冰融化和高浮游植物生产力的情况。在其他地区，高 DMS 浓度通常伴随着更高的叶绿素和ΔO/Ar。阿蒙森海表层水中 DMS 和初级生产力的大空间变异性似乎归因于海冰的融化条件、作为 DMS 产生者的南极磷虾的相对优势以及浮游植物大量繁殖和随后 DMS 产生之间的时间差异。DMS 和ΔO/Ar 的深度剖面与水平表面数据一致，表现出明显的空间变异性。然而，尽管存在很大的空间变异性，但与 2009 年的先前结果相反，在两个主要区域——海冰区和冰间湖区，表层水中的 DMS 浓度和ΔO/Ar 没有明显区别。这种差异可能与浮游植物组合的年际变化以及海冰条件、开花期和在广阔的阿蒙森海表面面积上的空间覆盖范围的差异有关。
