Data from: Ectomycorrhizal and saprotrophic fungi respond differently to long-term experimentally increased snow depth in the High Arctic

Changing climate is expected to alter precipitation patterns in the Arctic, with consequences for subsurface temperature and moisture conditions, community structure, and nutrient mobilization through microbial belowground processes. Here, we address the effect of increased snow depth on the variation in species richness and community structure of ectomycorrhizal (ECM) and saprotrophic fungi. Soil samples were collected weekly from mid-July to mid-September in both control and deep snow plots. Richness of ECM fungi was lower, while saprotrophic fungi was higher in increased snow depth plots relative to controls. [Correction added on 23 September 2016 after first online publication: In the preceding sentence, the richness of ECM and saprotrophic fungi were wrongly interchanged and have been fixed in this current version.] ECM fungal richness was related to soil NO3-N, NH4-N, and K; and saprotrophic fungi to NO3-N and pH. Small but significant changes in the composition of saprotrophic fungi could be attributed to snow treatment and sampling time, but not so for the ECM fungi. Delayed snow melt did not influence the temporal variation in fungal communities between the treatments. Results suggest that some fungal species are favored, while others are disfavored resulting in their local extinction due to long-term changes in snow amount. Shifts in species composition of fungal functional groups are likely to affect nutrient cycling, ecosystem respiration, and stored permafrost carbon.

气候变化预计将改变北极地区的降水格局，并通过地下微生物过程对地下温湿度状况、群落结构以及养分活化产生一系列影响。本研究探讨了积雪深度增加对外生菌根（ectomycorrhizal, ECM）真菌与腐生真菌的物种丰富度及群落结构变异的调控效应。研究于7月中旬至9月中旬期间，每周在对照样地与增雪样地中采集土壤样品。相较于对照样地，增雪样地的外生菌根真菌丰富度更低，而腐生真菌丰富度更高。【2016年9月23日首次在线发表后更正：前文语句中外生菌根与腐生真菌的丰富度描述曾被颠倒，本版本已完成修正。】外生菌根真菌丰富度与土壤硝态氮（NO3-N）、铵态氮（NH4-N）及钾元素含量显著相关；腐生真菌丰富度则与土壤硝态氮及pH值相关。积雪处理与采样时间可对腐生真菌的群落组成产生小幅但显著的影响，但对外生菌根真菌未观察到类似效应。积雪融化延迟并未对不同处理组间真菌群落的时间变异产生显著影响。研究结果表明，积雪量的长期变化会使部分真菌物种获得生存优势，而另一些物种则因竞争劣势发生局部灭绝。真菌功能群的物种组成转变，可能会对养分循环、生态系统呼吸以及永久冻土储碳过程产生潜在影响。