School of BioSciences, University of Melbourne, Melbourne, Victoria, Australia.
Fisheries and Oceans Canada, Arctic and Aquatic Research Division, Winnipeg, Manitoba, Canada.
Glob Chang Biol. 2022 Jun;28(11):3711-3727. doi: 10.1111/gcb.16142. Epub 2022 Mar 8.
The Arctic is among the fastest-warming areas of the globe. Understanding the impact of climate change on foundational Arctic marine species is needed to provide insight on ecological resilience at high latitudes. Marine forests, the underwater seascapes formed by seaweeds, are predicted to expand their ranges further north in the Arctic in a warmer climate. Here, we investigated whether northern habitat gains will compensate for losses at the southern range edge by modelling marine forest distributions according to three distribution categories: cryophilic (species restricted to the Arctic environment), cryotolerant (species with broad environmental preferences inclusive but not limited to the Arctic environment), and cryophobic (species restricted to temperate conditions) marine forests. Using stacked MaxEnt models, we predicted the current extent of suitable habitat for contemporary and future marine forests under Representative Concentration Pathway Scenarios of increasing emissions (2.6, 4.5, 6.0, and 8.5). Our analyses indicate that cryophilic marine forests are already ubiquitous in the north, and thus cannot expand their range under climate change, resulting in an overall loss of habitat due to severe southern range contractions. The extent of marine forests within the Arctic basin, however, is predicted to remain largely stable under climate change with notable exceptions in some areas, particularly in the Canadian Archipelago. Succession may occur where cryophilic and cryotolerant species are extirpated at their southern range edge, resulting in ecosystem shifts towards temperate regimes at mid to high latitudes, though many aspects of these shifts, such as total biomass and depth range, remain to be field validated. Our results provide the first global synthesis of predicted changes to pan-Arctic coastal marine forest ecosystems under climate change and suggest ecosystem transitions are unavoidable now for some areas.
北极是全球变暖最快的地区之一。了解气候变化对基础北极海洋物种的影响，对于提供高纬度地区生态弹性的洞察力是必要的。在温暖的气候下，海藻形成的水下海洋森林预计将在北极进一步向北扩展其范围。在这里，我们通过根据三种分布类别（仅限于北极环境的物种、具有广泛环境偏好的物种但不限于北极环境和仅限于温带条件的物种）对海洋森林分布进行建模，来研究北方栖息地的增加是否可以弥补南方分布范围的减少。使用堆叠的 MaxEnt 模型，我们预测了在排放增加的代表性浓度路径情景（2.6、4.5、6.0 和 8.5）下，现代和未来海洋森林的当前适宜栖息地范围。我们的分析表明，耐寒性海洋森林已经在北部无处不在，因此在气候变化下无法扩展其范围，导致由于南部分布范围严重收缩而导致栖息地总体丧失。然而，预计北极盆地内的海洋森林范围在气候变化下仍将基本保持稳定，除了一些地区，特别是加拿大群岛，会有明显的例外。在某些地区，随着耐寒和耐寒物种在南部分布范围的灭绝，可能会发生演替，导致中高纬度地区的生态系统向温带气候转变，尽管这些转变的许多方面，如总生物量和深度范围，仍有待实地验证。我们的结果提供了气候变化下泛北极沿海海洋森林生态系统预测变化的首次全球综合分析，并表明现在某些地区的生态系统转变是不可避免的。
