Pathogen-induced tree mortality modifies key components of the C and N cycles with no changes on microbial functional diversity

Here we assessed the effects of Quercus suber dieback, caused by the exotic root pathogen Phytophthora cinnamomi, on the soil microbial community and key components of the C and N cycle. We used a spatially-explicit neighbourhood approach to analyse the effects of Q. suber trees with different health status and non-declining coexistent species on soil variables. The study was replicated in the two main Q. suber forest types of the region (closed forests and open woodlands) with contrasting soil texture characteristics. Pathogen-induced tree dieback did not affect microbial functional diversity or biomass, but translated into lower soil microbial respiration. Tree mortality induced changes in several variables of the C and N cycle, but the sign and magnitude of these effects varied depending on the local characteristics of soil texture. Coexistent species differed strongly from Q. suber in their effects on the C and N cycle. Overall, our results show that tree dieback due to invasive pathogens translates into complex short- and long-term effects on different components of the C and N cycles, despite no effects on microbial functional diversity and biomass.

There are two spreadsheets with data. The spreadsheet "soil dataset" contains raw soil data. The spreadsheet "tree dataset" contains the information about neighbour trees (species, position, size and defoliation index). After each data spreadsheet, there is a spreadsheet with the associated metadata, where a description of all the variables and units can be found.

本研究评估了由外来根病原菌樟疫霉（Phytophthora cinnamomi）引起的栓皮栎（Quercus suber）枯梢病对土壤微生物群落及碳（C）、氮（N）循环关键组分的影响。我们采用空间显式邻域分析方法，探究不同健康状态的栓皮栎植株以及共存的未枯梢伴生树种对土壤变量的影响。本研究在该区域两种主要栓皮栎林型——郁闭林与开阔疏林——中开展重复实验，两类林型的土壤质地特征存在显著差异。病原菌诱导的树木枯梢并未对微生物功能多样性或生物量造成影响，但会导致土壤微生物呼吸速率降低。树木死亡会改变碳、氮循环的多项变量，但此类影响的方向与强度取决于土壤质地的局地特征。伴生树种对碳、氮循环的影响与栓皮栎存在显著差异。总体而言，本研究结果表明，尽管入侵性病原菌引发的树木枯梢未对微生物功能多样性与生物量产生影响，但其会对碳、氮循环的不同组分造成复杂的短期与长期影响。
本数据集包含两张数据表。其中“土壤数据集（soil dataset）”收录原始土壤数据；“树木数据集（tree dataset）”则包含邻域树木的相关信息，涵盖物种、位置、植株大小与落叶指数。每张数据表后均附带一张元数据表，其中可查询所有变量的描述与单位信息。