The Southern Ocean is undergoing rapid environmental changes that are likely to have a profound impact on marine life, as organisms are adapted to sub-zero temperatures and display specific adaptations to polar conditions. However, species ecological and physiological responses to environmental changes remain poorly understood at large spatial scale owing to sparse observation data. In this context, correlative ecological niche modeling (ENMc) can prove useful. This approach is based on the correlation between species occurrences and environmental parameters to predict the potential species occupied space. However, this approach suffers from a series of limitations amongst which extrapolation and poor transferability performances in space and time. Mechanistic ecological niche modeling (ENMm) is a process-based approach that describes species functional traits in a dynamic environmental context and can therefore represent a complementary tool to understand processes that shape species distribution in a changing environment. In this study, we used both ENMc and ENMm projections to model the distribution of the Antarctic echinoid Sterechinus neumayeri. Both models were projected according to present (2005–2012) and future IPCC scenarios RCP 4.5 and 8.5 for (2050–2099). ENMc and ENMm projections are congruent and predict suitable current conditions for the species on the Antarctic shelf, in the Ross Sea and Prydz Bay areas. Unsuitable conditions are predicted in the northern Kerguelen Plateau and South Campbell Plateau due to observed lower food availability and higher sea water temperatures compared to other areas. In contrast, the two models diverge under future RCP 4.5 and 8.5 scenarios. According to ENMm projections, the species would not be able to grow nor reach sexual maturity over the entire ocean, whereas the Antarctic shelf is still projected as suitable by the ENMc. This study highlights the complementarity and relevance of EMN approaches to model large scale distribution patterns and assess species sensitivity and potential response to future environmental conditions.

南大洋正在经历快速的环境变化，这可能对海洋生物产生深远的影响，因为生物体适应了零度以下的温度并表现出对极地条件的特定适应。然而，由于观测数据稀少，物种对环境变化的生态和生理反应在大空间尺度上仍然知之甚少。在这种情况下，相关生态位模型 (ENMc) 可以证明是有用的。这种方法基于物种出现与环境参数之间的相关性来预测潜在物种占据的空间。然而，这种方法受到一系列限制，其中包括外推和空间和时间的可转移性差。机械生态位建模 (ENMm) 是一种基于过程的方法，它描述了动态环境背景下的物种功能特征，因此可以作为一种补充工具来了解在不断变化的环境中塑造物种分布的过程。在这项研究中，我们使用 ENMc 和 ENMm 投影来模拟南极海胆的分布新氏留念线虫. 两种模型均根据当前（2005-2012）和未来 IPCC 情景 RCP 4.5 和 8.5（2050-2099）进行预测。ENMc 和 ENMm 预测是一致的，并预测了南极大陆架、罗斯海和普里兹湾地区适合该物种的当前条件。与其他地区相比，由于观测到的食物供应量较低且海水温度较高，因此预计凯尔盖朗高原北部和南坎贝尔高原将出现不适宜的条件。相比之下，这两种模型在未来的 RCP 4.5 和 8.5 情景下存在分歧。根据 ENMm 的预测，该物种将无法在整个海洋中生长或达到性成熟，而 ENMc 仍预测南极大陆架是合适的。