Glacier melting sediment inputs affect coastal ecosystems on the Antarctic Peninsula. In Potter Cove (South Shetland Islands, Antarctica), the shift from an “ascidian dominated” to a “mixed” assemblage has been linked to sedimentation. However, in recently described newly ice-free areas ascidians became dominant in spite of total suspended particulate matter (TSPM) concentrations, which are the highest measured in Potter Cove. Here, we compared the gut content and energy reserve of three ascidian species at three stations under different TSPM regimes. All analyzed species had a higher gut content with lower %OM at these newly areas. A theoretical relationship between the scope for growth for the targeted ascidians and TSPM explained assemblages' recorded change but failed to explain current ascidians distribution. The results may indicate the existence of a TSPM threshold that allows the spatial coexistence of alternative stable states at benthic Potter Cove system.

冰川融化的沉积物输入会影响南极半岛的沿海生态系统。在Potter Cove（南极南设得兰群岛），从“以海底为主”到“混合”组合的转变与沉积有关。但是，在最近描述的新的无冰地区，尽管总悬浮颗粒物（TSPM）浓度达到最高水平，但海鸟仍占主导地位。在这里，我们比较了在不同TSPM体制下三个站点的三种海鞘物种的肠道含量和能量储备。在这些新区域，所有分析物种的肠道含量都较高，而％OM较低。目标海生动物的生长范围和TSPM之间的理论关系解释了组合的记录变化，但未能解释当前海生动物的分布。