Kelps are canopy-forming brown seaweed sustaining critical ecosystem services in coastal habitats, including shelter and nursery grounds, and providing food resources to a myriad of associated species. This study modeled the fundamental niche of Laminaria abyssalis along the Brazilian continental margin, an endemic species of the South Atlantic, to anticipate potential distributional range shifts under two contrasting scenarios of future environmental changes (RCP2.6 and RCP8.5). The model for fundamental niche predictions considering the “present scenario” has shown a wider potential area than the realized niche (i.e., the area where the species actually occurs) along the Brazilian coast. In both future scenarios, the models have shown niche erosion on the northern portion of the Brazilian coast and niche gains towards the south. In both scenarios, L. abyssalis populations tend to shift to deeper regions of the reef. Considering the restricted range of occurrence (33,000 km²) and intense anthropic activities along these beds, such as trawling fisheries, oil/gas mining, or removal for agricultural purposes, acting synergically with global warming, may drive this ecosystem to collapse faster than kelp species’ ability to adapt. We propose to classify L. abyssalis as Endangered - (EN) under IUCN criteria. As well as highlight that long-term monitoring of kelp beds is an urgent need to develop effective conservation initiatives to protect such rare and invaluable ecosystems.

海带是形成树冠的棕色海藻，维持着沿海栖息地的关键生态系统服务，包括庇护所和苗圃，并为无数相关物种提供食物资源。这项研究模拟了巴西大陆边缘的深海昆布（南大西洋特有物种）的基本生态位，以预测未来环境变化的两种对比情景（RCP2.6 和 RCP8.5）下潜在的分布范围变化。考虑到“当前情景”的基本生态位预测模型显示，巴西海岸的潜在区域比已实现的生态位（即物种实际出现的区域）更广泛。在这两种未来情景中，模型都显示了巴西海岸北部地区的生态位侵蚀和南部地区的生态位增加。在这两种情况下，深海潜鱼种群都倾向于转移到珊瑚礁的更深区域。考虑到发生范围有限（33,000 km ² ）和这些河床沿线的强烈人类活动，例如拖网渔业、石油/天然气开采或出于农业目的的清除，与全球变暖的协同作用，可能会导致该生态系统比海带更快地崩溃物种的适应能力。我们建议根据 IUCN 标准将L. abyssalis列为濒危物种 - (EN)。并强调对海藻床的长期监测迫切需要制定有效的保护举措来保护这种稀有且宝贵的生态系统。