Department of Ecological and Biological Sciences, University of Tuscia, Largo dell'Università, 01100 Viterbo, Italy.
Laboratory of Environmental Microbiology, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 14220 Praha 4, Czech Republic.
FEMS Microbiol Ecol. 2022 Mar 24;98(3). doi: 10.1093/femsec/fiac025.
As the European Alps are experiencing a strong climate warming, this study analyzed the soil microbiome at different altitudes and among different vegetation types at the Stelvio Pass (Italian Alps), aiming to (i) characterize the composition and functional potential of the microbiome of soils and their gene expression during the peak vegetative stage; (ii) explore the potential short-term (using open-top chambers) and long-term (space-for-time substitutions) effects of increasing temperature on the alpine soil microbiome. We found that the functional potential of the soil microbiome and its expression differed among vegetation types. Microbial α-diversity increased along the altitudinal gradient. At lower altitude, shrubland had the highest proportion of fungi, which was correlated with higher amounts of CAZymes, specific for degrading fungal biomass and recalcitrant plant biopolymers. Subalpine upward vegetation shift could lead a possible loss of species of alpine soils. Shrub encroachment may accelerate higher recalcitrant C decomposition and reduce total ecosystem C storage, increasing the efflux of CO2 to the atmosphere with a positive feedback to warming. A total of 5 years of warming had no effect on the composition and functioning of microbial communities, indicating that longer-term warming experiments are needed to investigate the effects of temperature increases on the soil microbiome.
随着欧洲阿尔卑斯山经历强烈的气候变暖，本研究在意大利阿尔卑斯山的斯泰尔维奥山口（Stelvio Pass）分析了不同海拔高度和不同植被类型的土壤微生物组，旨在：（i）描述土壤微生物组的组成和功能潜力及其在植被高峰期的基因表达；（ii）探索短期（使用开顶式气室）和长期（时空替代）增温对高山土壤微生物组的潜在影响。我们发现，土壤微生物组的功能潜力及其表达因植被类型而异。微生物 α 多样性沿海拔梯度增加。在较低的海拔处，灌木林的真菌比例最高，这与降解真菌生物量和难降解植物生物聚合物的 CAZymes 数量较高有关。亚高山向上的植被转变可能导致高山土壤物种的可能丧失。灌木林的侵入可能会加速更高的难降解 C 分解，并减少总生态系统 C 储存，从而增加 CO2 向大气的排放，对变暖产生正反馈。总计 5 年的增温对微生物群落的组成和功能没有影响，这表明需要进行更长时间的增温实验来研究温度升高对土壤微生物组的影响。
