LABEM - Laboratory of Biotechnology and Microbial Ecology, Institute of Microbiology Paulo de Góes, Department of General Microbiology, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
Embrapa Soils, Rio de Janeiro, Brazil.
Sci Rep. 2020 Jun 3;10(1):9075. doi: 10.1038/s41598-020-66004-x.
Agriculture, forestry and other land uses are currently the second highest source of anthropogenic greenhouse gases (GHGs) emissions. In soil, these gases derive from microbial activity, during carbon (C) and nitrogen (N) cycling. To investigate how Eucalyptus land use and growth period impact the microbial community, GHG fluxes and inorganic N levels, and if there is a link among these variables, we monitored three adjacent areas for 9 months: a recently planted Eucalyptus area, fully developed Eucalyptus forest (final of rotation) and native forest. We assessed the microbial community using 16S rRNA gene sequencing and qPCR of key genes involved in C and N cycles. No considerable differences in GHG flux were evident among the areas, but logging considerably increased inorganic N levels. Eucalyptus areas displayed richer and more diverse communities, with selection for specific groups. Land use influenced communities more extensively than the time of sampling or growth phase, although all were significant modulators. Several microbial groups and genes shifted temporally, and inorganic N levels shaped several of these changes. No correlations among microbial groups or genes and GHG were found, suggesting no link among these variables in this short-rotation Eucalyptus study.
农业、林业和其他土地利用目前是人为温室气体（GHG）排放的第二大来源。在土壤中，这些气体源自微生物活动，发生在碳（C）和氮（N）循环过程中。为了研究桉树的土地利用和生长周期如何影响微生物群落、温室气体通量和无机氮水平，以及这些变量之间是否存在联系，我们对三个相邻区域进行了为期 9 个月的监测：一个新种植的桉树区域、完全发育的桉树林（轮伐末期）和原生林。我们使用 16S rRNA 基因测序和参与 C 和 N 循环的关键基因的 qPCR 来评估微生物群落。在这些区域之间，温室气体通量没有明显差异，但采伐大大增加了无机氮水平。桉树区的群落更加丰富多样，对特定群体具有选择性。土地利用对群落的影响比采样时间或生长阶段更为广泛，尽管所有这些因素都是重要的调节因素。一些微生物群和基因随时间发生变化，无机氮水平影响了其中的一些变化。未发现微生物群或基因与 GHG 之间存在相关性，这表明在这个短期轮伐桉树研究中，这些变量之间没有联系。
