Département de biologie, Québec Océan and Takuvik Joint International Laboratory (UMI 3376), Université Laval (Canada) - CNRS (France), Université Laval, Québec, QC, G1V 0A6, Canada.
Institut de biologie intégrative et des systèmes (IBIS), Université Laval, Québec, QC, GIV 0A6, Canada.
Sci Rep. 2018 Jun 20;8(1):9405. doi: 10.1038/s41598-018-27705-6.
Oceanic gateways are sensitive to climate driven processes. By connecting oceans, they have a global influence on marine biological production and biogeochemical cycles. The furthest north of these gateways is Nares Strait at the top of the North Water between Greenland and Ellesmere Island (Canada). This gateway is globally beneficial, first by supporting high local mammal and bird populations and second with the outflow of phosphate-rich Arctic waters fueling the North Atlantic spring bloom. Both sides of the North Water are hydrologically distinct with counter currents that make this Arctic portal a Janus gateway, after Janus, the Roman god of duality. We examined oceanographic properties and differences in phytoplankton and other protist communities from the eastern and western sides of the North Water (latitude 76.5°N) and found that species differed markedly due to salinity stratification regimes and local hydrography. Typical Arctic communities were associated with south flowing currents along the Canadian side, while potentially noxious Pseudo-nitzschia spp. were dominant on the Greenland side and associated with greater surface freshening from ice melt. This susceptibility of the Greenland side to Pseudo-nitzschia spp. blooms suggest that monitoring species responses to climate mediated changes is needed.
海洋门户对气候驱动的过程很敏感。通过连接海洋，它们对海洋生物生产力和生物地球化学循环具有全球影响。这些门户中最靠北的是格陵兰和埃尔斯米尔岛（加拿大）之间的北水域顶部的纳尔斯海峡。这个门户具有全球性的益处，首先是支持高当地哺乳动物和鸟类的数量，其次是富含磷酸盐的北极水的流出为北大西洋春季藻华提供了燃料。北水域的两侧在水文学上是不同的，逆流使得这个北极门户成为一个两面神门户，以两面神，罗马的二元神命名。我们研究了来自北水域（北纬 76.5°）东侧和西侧的海洋物理特性和浮游植物及其他原生生物群落的差异，发现由于盐度分层和当地水文学的不同，物种有明显的差异。典型的北极群落与沿着加拿大一侧的南向水流有关，而潜在的有害伪菱形藻属则在格陵兰一侧占主导地位，并且与更多的冰融化导致的表面淡化有关。格陵兰一侧对伪菱形藻属大量繁殖的敏感性表明，需要监测物种对气候介导的变化的反应。
