The Distribution and Turnover of Bacterial Communities in the Root Zone of Seven Stipa Species Across an Arid and Semi-arid Steppe.
The Distribution and Turnover of Bacterial Communities in the Root Zone of Seven Stipa Species Across an Arid and Semi-arid Steppe.
复制标题
干旱半干旱草原七种针茅根区细菌群落的分布和更新
DOI：
10.3389/fmicb.2021.782621
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发表时间：
2021
影响因子：
5.2
通讯作者：
Bao Y
中科院分区：
文献类型：
--
作者：
Ma X;Chao L;Li J;Ding Z;Wang S;Li F;Bao Y
根区土壤细菌群落能够调节重要的生态地球化学循环和植物生长演替。针茅作为草地建群种，受东西部湿度和南北部热量差异的制约，表现出种群的替代分布。根区细菌群落沿着大空间梯度的分布、周转、潜在驱动因子及其生态学意义尚不清楚。采用高通量测序技术结合多环境参数的测定，对干旱半干旱草原区7种针茅属植物根际土壤进行了研究。根区土壤细菌群落具有较大的更替性，土壤细菌群落结构沿着针茅类群过渡的规律性变化主要受气候、植被覆盖度和pH等因素的影响。细菌群落具有明显的针茅种群特异性，但受主要年降水量的影响更大，表现出沿着降水梯度的地理分布格局，其中以放线菌、酸杆菌、变形菌和绿弯菌最为丰富。在针茅类群由东向西的转化过程中，根区细菌群落多样性表现出先下降，后急剧上升的趋势。短花型，随后向西北方向持续减少。不同针茅种间存在着不同的细菌类群间的相互作用，其中S. krylovii的互作网络最简单、最稳定，对环境和S.短花型最复杂、最不稳定。在一定时期内，细菌群落主要受扩散限制的影响。研究结果有助于半干旱草原生态系统可持续服务功能的预测和微生物资源的保护。
The bacterial communities of the root-zone soil are capable of regulating vital biogeochemical cycles and the succession of plant growth. Stipa as grassland constructive species is restricted by the difference features of east–west humidity and north–south heat, which shows the population substituting distribution. The distribution, turnover, and potential driving factors and ecological significance of the root-zone bacterial community along broad spatial gradients of Stipa taxa transition remain unclear. This paper investigated seven Stipa species root-zone soils based on high-throughput sequencing combined with the measurements of multiple environmental parameters in arid and semi-arid steppe. The communities of soil bacteria in root zone had considerable turnover, and some regular variations in structure along the Stipa taxa transition are largely determined by climatic factors, vegetation coverage, and pH at a regional scale. Bacterial communities had a clear Stipa population specificity, but they were more strongly affected by the main annual precipitation, which resulted in a biogeographical distribution pattern along precipitation gradient, among which Actinobacteria, Acidobacteria, Proteobacteria, and Chloroflexi were the phyla that were most abundant. During the transformation of Stipa taxa from east to west, the trend of diversity shown by bacterial community in the root zone decreased first, and then increased sharply at S. breviflora, which was followed by continuous decreasing toward northwest afterwards. However, the richness and evenness showed an opposite trend, and α diversity had close association with altitude and pH. There would be specific and different bacterial taxa interactions in different Stipa species, in which S. krylovii had the simplest and most stable interaction network with the strongest resistance to the environment and S. breviflora had most complex and erratic. Moreover, the bacterial community was mainly affected by dispersal limitation at a certain period. These results are conducive to the prediction of sustainable ecosystem services and protection of microbial resources in a semi-arid grassland ecosystem.