We examined the effect of glacial melt-related retreat environmental conditions on the spatial heterogeneity of food sources for Antarctic nearshore marine benthic communities of Potter Cove, a representative fjord on King George Island on the West Antarctic Peninsula. Focusing on Antarctic suspension feeders, we surveyed the variation of carbon (δ¹³C) and nitrogen (δ¹⁵N) stable isotopes in three different stations with contrasting characteristics in terms of glacier-sedimentary regimes and distance from the glacier. Bayesian mixing models were used to estimate the relative contribution of eight potential food sources at the study sites and to the consumers' diet. The isotopically signatures of suspension feeders displayed a broad range of assimilate available food sources with distinct contributions at each site. Overall, for most of the suspension feeders analysed, contributions of suspended particulate matter and macroalgae detritus tended to prevail over the rest of the potential food sources. Additionally, we confirm the assimilation of krill faeces by benthic organisms reinforcing its relevance as food source in nearshore Antarctic ecosystems. Mixing models corroborated the influence of glacier discharge on the spatial distribution of available food sources, since their contribution in the suspension feeders diet was different and more heterogeneous in the internal stations (ice-proximal zone) than in the external one (ice-distal zone). The analysis of isotopic signatures of primary benthic consumers (suspension feeders) indicated the spatial heterogeneity of food sources and its composition in coastal Antarctic nearshore, as consequence of the glacial influence on the local environment and hydrology.

我们研究了冰川融化相关的退缩环境条件对南极洲波特波特湾南极近岸海洋底栖生物群落食物源空间异质性的影响，该峡湾是南极半岛西乔治岛的代表峡湾。着眼于南极悬浮液供料器，我们调查碳的变化（δ ¹³ C）和氮（δ ¹⁵N）在三个不同站点的稳定同位素，它们在冰川沉积方式和与冰川的距离方面具有鲜明的特征。贝叶斯混合模型用于估计研究地点的八种潜在食物来源和消费者饮食的相对贡献。悬浮喂食器的同位素特征显示出广泛的同化可利用的食物来源，在每个位置都有不同的贡献。总体而言，对于大多数经过分析的悬浮喂食器，悬浮颗粒物和大型藻类碎屑的贡献往往占其余潜在食物来源的比重。此外，我们证实底栖生物对磷虾粪便的吸收增强了其在南极近岸生态系统中作为食物来源的相关性。混合模型证实了冰川释放对可用食物源空间分布的影响，因为它们在悬浮喂食器饮食中的贡献是不同的，并且内部站（近冰区）比外部站（冰远区）更不均匀）。对主要底栖生物消费者（悬浮饲养者）的同位素特征的分析表明，由于冰川对当地环境和水文学的影响，南极沿海近岸食物来源的空间异质性及其组成。