放牧和刈割对大针茅草原土壤微生物群落结构及多样性的影响

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 放牧和刈割对大针茅草原土壤微生物群落结构及多样性的影响 DOI: 10.5846/stxb202103290818 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 内蒙古自治区科技计划项目（2019ZD008）；内蒙古自治区自然科学基金项目（2020ZD03）；国家自然科学基金项目（31861143001，32160332） Effects of management regime on soil microbial community structure and diversity of Stipa grandis grassland Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:放牧和刈割是内蒙古草原的两种主要利用方式，然而，长期放牧和刈割对大针茅草原土壤微生物群落的影响知之甚少，因此，以内蒙古大针茅草原为研究对象，设置放牧和刈割两种利用方式，以围封不利用为对照，基于高通量测序技术，研究大针茅草原在不同利用方式下土壤微生物组成及多样性的变化，并结合土壤理化因子进一步探究土壤微生物群落组成的主要影响因素。研究结果表明：不同利用方式下土壤细菌α多样性指数无显著差异，而刈割显著提高了土壤真菌Observed_species、Chao1和ACE指数；土壤细菌群落的优势菌门是变形菌门（Proteobacteria）和放线菌门（Actinobacteria），土壤真菌群落的优势菌门是子囊菌门（Ascomycota）和被孢霉门（Mortierellomycota），不同利用方式下部分微生物类群的相对丰度差异显著，放牧显著提高了细菌群落的变形菌门、疣微菌门（Verrucomicrobia）和芽单胞菌门（Gemmatimonadetes）的相对丰度，刈割显著提高了真菌群落的担子菌门（Basidiomycota）相对丰度，此外，放牧和刈割均显著降低了厚壁菌门（Firmicutes）的相对丰度；冗余分析表明，土壤细菌主要受硝态氮和铵态氮影响，二者均与酸杆菌门（Acidobacteria）呈正相关，与变形菌门（Proteobacteria）呈负相关，土壤真菌主要受有效磷和硝态氮影响。综上所述，草地利用方式的改变通过土壤理化因子改变了土壤微生群落组成及多样性，其中土壤铵态氮、硝态氮和有效磷是微生物群落形成和演化的主要驱动因素。研究揭示了不同利用方式下大针茅草原土壤微生物群落结构特征及多样性的变化及其与土壤理化性质的关系，可为大针茅草原合理利用提供理论依据。 Abstract:Grazing and mowing are two dominant management regimes in the Inner Mongolia grassland, both of which have a profound impact on grassland ecosystem, and most of the previous studies have primarily focused on the effects on plant and soil. Soil microbial communities are the most abundant and diverse groups of organisms on earth and are responsible for numerous key ecosystem processes. They play an important role in the circulation of materials and nutrients between plants and soil ecosystems. However, their response to these management regimes has not been comprehensively explored in Stipa grandis grassland. In this study, two management regimes of grazing and mowing were set up in a typical S. grandis area, and enclosure was used as the control. Based on high-throughput sequencing technology, the changes of soil microbial composition and diversity under different management regimes was examined, Redundancy analysis was used to analysis soil physical and chemical characteristics influencing on it. The results showed that there was no significant difference in soil bacterial α diversity index under different management regimes, but mowing significantly increased soil fungal Observed_species, Chao1 and ACE index. Amplicon sequencing revealed Proteobacteria and Actinobacteria were the dominant bacterial phylum under different grassland management regimes, and the dominant phyla of soil fungal communities were Ascomycota and Mortierellomycota. Grazing significantly increased the relative abundance of Proteobacteria, Verrucomicrobia and Gemmatimonadetes of the bacterial community, and mowing significantly increased the relative abundance of Basidiomycota of fungal community. In addition, grazing and mowing significantly reduced the relative abundance of Firmicutes. Redundancy analysis showed that soil bacteria were mainly affected by nitrate nitrogen and ammonium nitrogen, which were positively correlated with Acidobacteria and negatively correlated with Proteobacteria. Soil fungi were mainly affected by available phosphorus and nitrate nitrogen. In conclusion, changes in grassland usage methods altered the composition and diversity of soil microflora through soil physicochemical factors, and soil ammonium nitrogen, nitrate nitrogen and available phosphorus were the main driving factors on microbial community formation and evolution. This study revealed the structural characteristics and diversity of soil microbial communities in the S. grandis steppe under different management regimes and their relationship with soil physicochemical properties, which may provide a theoretical basis for the rational utilization of S. grandis steppe. 参考文献 相似文献 引证文献