Boué Cédric, DeBellis Tonia, Venier Lisa A, Work Timothy T, Kembel Steven W
Département des Sciences Biologiques, University of Québec at Montreal, Montréal, QC, Canada.
Department of Biology, Concordia University, Montreal, QC, Canada.
PeerJ. 2019 Dec 13;7:e8027. doi: 10.7717/peerj.8027. eCollection 2019.
Growing pressures linked to global warming are prompting governments to put policies in place to find alternatives to fossil fuels. In this study, we compared the impact of tree-length harvesting to more intensive full-tree harvesting on the composition of fungi residing in residual stumps 5 years after harvest. In the tree-length treatment, a larger amount of residual material was left around the residual stumps in contrast to the full-tree treatment where a large amount of woody debris was removed. We collected sawdust from five randomly selected residual stumps in five blocks in each of the tree-length and full-tree treatments, yielding a total of 50 samples (25 in each treatment). We characterized the fungal operational taxonomic units (OTUs) present in each stump using high-throughput DNA sequencing of the fungal ITS region. We observed no differences in Shannon diversity between tree-length and full-tree harvesting. Likewise, we observed few differences in the composition of fungal OTUs among tree-length and full-tree samples using non-metric multidimensional scaling. Using the differential abundance analysis implemented with DESeq2, we did, however, detect several associations between specific fungal taxa and the intensity of residual biomass harvest. For example, (Bres.) KH Larss. and sp. were found mainly in the full-tree treatment, while (Pers.) Bres. and (Grove) Crous & Arzanlou were found mainly in the tree-length treatment. While none of the 20 most abundant species in our study were identified as pathogens we did identify one conifer pathogen species (Fr.) P. Karst found mainly in the full-tree treatment.
与全球变暖相关的压力不断增加，促使各国政府出台政策，寻找化石燃料的替代品。在本研究中，我们比较了伐根收获与更集约的全树收获对采伐后5年残留树桩中真菌群落组成的影响。在伐根处理中，残留树桩周围留下了大量的残余物，而在全树处理中，大量的木质碎片被清除。我们在伐根处理和全树处理的每个五个区组中，从五个随机选择的残留树桩中收集锯末，共获得50个样本（每个处理25个）。我们使用真菌ITS区域的高通量DNA测序对每个树桩中存在的真菌操作分类单元（OTU）进行了表征。我们观察到伐根收获和全树收获之间的香农多样性没有差异。同样，使用非度量多维标度法，我们观察到伐根和全树样本之间真菌OTU组成的差异很小。然而，使用DESeq2进行的差异丰度分析，我们确实检测到了特定真菌类群与残留生物量收获强度之间的几种关联。例如，（Bres.）KH Larss.和sp.主要出现在全树处理中，而（Pers.）Bres.和（Grove）Crous & Arzanlou主要出现在伐根处理中。虽然我们研究中最丰富的20个物种中没有一个被鉴定为病原体，但我们确实鉴定出一种针叶树病原体物种（Fr.）P. Karst主要出现在全树处理中。
