Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Gansu Province, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China.
State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China.
Arch Microbiol. 2021 Aug;203(6):2809-2823. doi: 10.1007/s00203-021-02272-z. Epub 2021 Mar 17.
Limited knowledge about the variation patterns of bacterial community composition in the sand and vegetative ecosystems confines our understanding regarding the contribution of the sand dune to desert areas. In this study, 454 pyrosequencing platforms were adopted to determine the community structure of bacteria and diversity of sand dunes in northeastern Qinghai-Tibet Plateau, China: 50 cm deep, rhizosphere, physical crusts, and biological crusts representing sand and vegetative ecosystems, respectively. The findings revealed significant variation in bacterial diversities and the structure of communities in the sand and vegetative ecosystems. The dominant bacterial phyla of sand and vegetative ecosystems were Firmicutes (47%), Actinobacteria (21%), Proteobacteria (16%), and Bacteroidetes (13%), while Lactococcus (50%) was found to be the dominant genus. Furthermore, samples with high alpha-diversity indices (Chao 1 and Shannon) for the vegetative ecosystem have the lowest modularity index and the largest number of biomarkers, with some exceptions. Redundancy analysis exhibited that environmental factors could explain 72% (phyla) and 67% (genera) of the bacterial communities, with EC, TC, and TOC being the major driving factors. This study expands our understanding of bacterial community composition in the desert ecosystem. The findings suggest that variations in the sand and vegetative ecosystems, such as those predicted by environmental factors, may reduce the abundance and diversity of bacteria, a response that likely affects the provision of key ecosystem processes by desert regions.
关于沙生植被生态系统中细菌群落组成变化模式的知识有限，限制了我们对沙丘对沙漠地区的贡献的理解。本研究采用 454 pyrosequencing 平台，分别代表沙生和植被生态系统，确定了中国青藏高原东北部沙丘的细菌群落结构和多样性：50cm 深处、根际、物理结皮和生物结皮。研究结果表明，沙生和植被生态系统中的细菌多样性和群落结构存在显著差异。沙生和植被生态系统的优势细菌门分别为厚壁菌门（Firmicutes）（47%）、放线菌门（Actinobacteria）（21%）、变形菌门（Proteobacteria）（16%）和拟杆菌门（Bacteroidetes）（13%），而乳球菌属（Lactococcus）（50%）是优势属。此外，植被生态系统具有较高的 alpha 多样性指数（Chao 1 和 Shannon）的样本具有最低的模块性指数和最多的生物标志物，有些例外。冗余分析表明，环境因素可以解释 72%（门）和 67%（属）的细菌群落，其中 EC、TC 和 TOC 是主要的驱动因素。本研究扩展了我们对沙漠生态系统中细菌群落组成的认识。研究结果表明，沙生和植被生态系统的变化，如环境因素所预测的那样，可能会降低细菌的丰度和多样性，这一反应可能会影响沙漠地区关键生态过程的提供。
