Rising atmospheric carbon dioxide is warming Arctic seawater at a rate twice the global average due to multiple positive feedbacks. Thus, warming is disproportionately influencing data‐poor Arctic marine ecosystems. Subarctic flora are an important component of these ecosystems, along with the less biodiverse flora endemic to the Arctic. Warming will likely lead to an increasing dominance of subarctic flora that will be initially successful due to a shorter sea ice period. Benthic crustose coralline algae presently flourishes in subarctic regions where they are key substrate builders that influence community structure through provision of habitat for a variety of benthic organisms. Here we evaluate changes in the skeletal resilience of long‐lived subarctic crustose coralline alga Clathromorphum compactum to variability in seawater temperature and sea ice (the later which influences salinity and solar irradiance reaching the seafloor) across latitudes in the northwest Atlantic and Arctic Oceans. We demonstrate that average growth and calcification rate significantly decreases in C. compactum toward higher latitudes due to colder temperatures and more fresh waters. Skeletal density also declines toward higher latitudes but displays specimen‐specific variability. However, through a common growth period (1984–2001), density increased at all locations which we interpret to be a response to warmer and more well‐lit benthic environments. At the most northerly site, growth and calcification also increased with density, suggesting warming and declining Arctic sea ice in the spring may benefit this species at its upper latitudinal limits. As a result, continued warming may enhance the presence of C. compactum in Arctic regions.

中文翻译：

---

北极地壳珊瑚藻对最近的环境变化具有韧性

由于多重积极反馈，大气中二氧化碳的增加使北极海水变暖的速度是全球平均水平的两倍。因此，变暖对缺乏资料的北极海洋生态系统产生了不成比例的影响。北极地区的植物区系是这些生态系统的重要组成部分，而北极地区特有的生物多样性较低的植物区系。气候变暖可能会导致北极圈内菌群优势的增加，由于较短的海冰期，这种作用最初将获得成功。底栖甲壳类珊瑚藻藻类目前在亚北极地区盛行，在那里它们是通过为各种底栖生物提供栖息地来影响群落结构的主要底物建设者。在这里，我们评估了长寿命的北极亚壳硬壳珊瑚藻藻Clathromorphum compactum的骨骼弹性变化。西北大西洋和北冰洋各纬度的海水温度和海冰变化（后者影响盐度和到达海底的太阳辐射）的变化。我们证明密实梭菌的平均生长和钙化速率显着降低由于温度较低和更多的淡水，因此朝向较高的纬度。骨骼密度也向较高的纬度下降，但显示出标本特定的变异性。但是，在一个共同的生长期（1984-2001年），所有地点的密度都在增加，我们认为这是对温暖和光线充足的底栖环境的反应。在最北端，生长和钙化也随密度增加而增加，这表明春季北极海冰的变暖和下降可能使该物种在其纬度上限处受益。结果，持续变暖可能会增加北极地区致密梭状芽胞杆菌的存在。