AUTHOR=Song Min , Peng Wanxia , Zeng Fuping , Du Hu , Peng Qin , Xu Qingguo , Chen Li , Zhang Fang 

TITLE=Spatial Patterns and Drivers of Microbial Taxa in a Karst Broadleaf Forest

JOURNAL=Frontiers in Microbiology

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2018.01691

DOI=10.3389/fmicb.2018.01691

ISSN=1664-302X

ABSTRACT=<p>Spatial patterns and drivers of soil microbial communities have not yet been well documented. Here, we used geostatistical modeling and Illumina sequencing of 16S rRNA genes to explore how the main microbial taxa at the phyla level are spatially distributed in a 25-ha karst broadleaf forest in southwest China. <italic>Proteobacteria</italic>, dominated by <italic>Alpha-</italic> and <italic>Deltaproteobacteria</italic>, was the most abundant phylum (34.51%) in the karst forest soils. Other dominating phyla were <italic>Actinobacteria</italic> (30.73%), and <italic>Acidobacteria</italic> (12.24%). Soil microbial taxa showed spatial dependence with an autocorrelation range of 44.4–883.0 m, most of them within the scope of the study plots (500 m). An increasing trend was observed for <italic>Alphaproteobacteria</italic>, <italic>Deltaproteobacteria</italic>, and <italic>Chloroflexi</italic> from north to south in the study area, but an opposite trend for <italic>Actinobacteria</italic>, <italic>Acidobacteira</italic>, and <italic>Firmicutes</italic> was observed. <italic>Thaumarchaeota</italic>, <italic>Bacteroidetes</italic>, <italic>Gemmatimonadetes</italic>, and <italic>Verrucomicrobia</italic> had patchy patterns, <italic>Nitrospirae</italic> had a unimodal pattern, and <italic>Latescibacteria</italic> had an intermittent pattern with low and high value strips. Location, soil total phosphorus, elevation, and plant density were significantly correlated with main soil bacterial taxa in the karst forest. Moreover, the total variation in soil microbial communities better explained by spatial factors than environmental variables. Furthermore, a large part of variation (76.8%) was unexplained in the study. Therefore, our results suggested that dispersal limitation was the primary driver of spatial pattern of soil microbial taxa in broadleaved forest in karst areas, and other environmental variables (i.e., soil porosity and temperature) should be taken into consideration.</p>