Lu Fan, Yi Boli, Ma Jun-Xiao, Wang Si-Nan, Feng Yu-Jie, Qin Kai, Tu Qiansi, Bu Zhao-Jun
Jiangsu Key Laboratory of Coal-Based Greenhouse Gas Control and Utilization, School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China.
Jilin Provincial Key Laboratory for Wetland Ecological Processes and Environmental Change in the Changbai Mountains, Institute for Peat and Mire Research, Renmin 5268, Changchun 130024, China.
Plants (Basel). 2025 Aug 2;14(15):2387. doi: 10.3390/plants14152387.
Peatlands store substantial amounts of carbon (C) in the form of peat, but are increasingly threatened by drought and shrub encroachment under climate warming. However, how peat decomposition and its temperature sensitivity () vary with depth and plant litter input under these stressors remains poorly understood. We incubated peat from two depths with different degrees of decomposition, either alone or incubated with divinum shoots or ovalifolia leaves, under five temperature levels and two moisture conditions in growth chambers. We found that drought and addition increased CO emissions in both peat layers, while affected only shallow peat. Deep peat alone or with exhibited higher than pure shallow peat. Drought increased the of both depths' peat, but this effect disappeared with fresh litter addition. The CO production rate showed a positive but marginal correlation with microbial biomass carbon, and it displayed a rather similar responsive trend to warming as the microbial metabolism quotient. These results indicate that both deep and dry peat are more sensitive to warming, highlighting the importance of keeping deep peat buried and waterlogged to conserve existing carbon storage. Additionally, they further emphasize the necessity of moss recovery following vascular plant encroachment in restoring carbon sink function in peatlands.
泥炭地以泥炭的形式储存着大量的碳（C），但在气候变暖的情况下，正日益受到干旱和灌木入侵的威胁。然而，在这些压力源下，泥炭分解及其温度敏感性（）如何随深度和植物凋落物输入而变化，仍知之甚少。我们在生长室的五个温度水平和两种水分条件下，将来自两个不同分解程度深度的泥炭单独培养，或与神香草嫩枝或卵叶泥炭藓叶一起培养。我们发现，干旱和添加神香草嫩枝增加了两个泥炭层的CO排放，而添加卵叶泥炭藓叶仅影响浅层泥炭。单独的深层泥炭或与神香草嫩枝一起的深层泥炭比纯浅层泥炭表现出更高的温度敏感性。干旱增加了两个深度泥炭的温度敏感性，但随着新鲜凋落物的添加，这种影响消失了。CO产生率与微生物生物量碳呈正相关但较弱，并且它与微生物代谢商一样，对变暖表现出相当相似的响应趋势。这些结果表明，深层和干燥的泥炭对变暖更敏感，突出了保持深层泥炭埋藏和积水以保护现有碳储存的重要性。此外，它们进一步强调了在泥炭地恢复碳汇功能时，在维管植物入侵后恢复泥炭藓的必要性。
