Substrate quality and not dominant plant community determines the vertical distribution and C assimilation of enchytraeids in peatlands

Peatlands are important carbon (C) stores as a result of acidity, waterlogging conditions and low temperatures slowing decomposition rates. However, climate change is predicted to bring not only changes in abiotic conditions, but also the replacement of peat-forming vegetation, such as Sphagnum mosses, with vascular plants. In these systems, enchytraeid worms represent the dominant mesofaunal group, and previous climate change manipulations have shown that their abundances and vertical distribution are strongly influenced by temperature and moisture gradients, with important implications for C cycling. Therefore, determining their behavioural responses to changes in both abiotic and biotic factors is crucial to quantify their contribution to decomposition processes. We investigated the importance of vertical edaphic gradients (soil moisture and labile C) on enchytraeids total numbers, vertical distribution and feeding activities by inverting intact soil cores and hence, reversing b...泥炭地是重要的碳（C）库，这是由于酸性环境、渍水条件与低温会延缓有机质的分解速率。然而，已有预测表明，气候变化不仅会改变非生物环境，还会使以泥炭藓（Sphagnum）为代表的泥炭形成植被被维管植物取代。在这类生态系统中，线蚓（enchytraeid）是优势中型土壤动物类群；此前开展的气候变化调控实验显示，其种群丰度与垂直分布深受温度与湿度梯度的影响，这对碳循环具有重要意义。因此，明确它们对非生物与生物因子变化的行为响应，对量化其在有机质分解过程中的贡献至关重要。 本研究通过翻转原状土柱以反转土壤垂直梯度（土壤湿度与活性碳），探究了该梯度对线蚓总数量、垂直分布及取食活动的调控作用，进而