摘要
土壤微生物在草地生态系统功能中发挥着重要作用,但其多样性对草地退化的响应尚未得到充分研究.采用宏基因组测序技术对五台山亚高山草甸4个不同退化阶段[未退化(ND)、轻度退化(LD)、中度退化(MD)和重度退化(HD)]土壤微生物分类和功能多样性特征及其影响因素进行分析.结果表明,4个不同退化阶段亚高山草甸之间放线菌门、拟杆菌门、硝化螺旋菌门和Parcubacteria的相对丰度存在显著差异(P<0.05).与ND草甸相比,退化草甸增加了与碳代谢、氨基酸生物合成、丙酮酸代谢、柠檬酸循环、丙酸代谢、丁酸代谢和脂肪酸代谢相关的基因比例,表明亚高山草甸退化改变了土壤微生物群落能量代谢和营养循环的潜力.草地退化改变了土壤微生物分类和功能α多样性,特别是MD和HD草甸中微生物功能多样性显著降低.亚高山草甸退化过程中土壤微生物物种分类和功能组成均显著变化(P<0.05).土壤总氮、pH值和有机质含量对微生物群落分类和功能组成具有显著影响.植物群落β多样性与微生物群落分类和功能β多样性显著相关(P<0.05),具有强耦合性.研究结果揭示了草地退化过程中地下微生物分类和功能多样性的变化及驱动机制,为亚高山草甸保护和生态修复提供了理论依据.
Although soil microbes play a key role in grassland ecosystem functioning,the response of their diversity to grassland degradation has not been fully investigated.Here,we used shotgun metagenomic sequencing to analyze the characteristics and influencing factors of soil microbial taxonomic and functional diversity at four different degradation stages[i.e.,non-degraded(ND),lightly degraded(LD),moderately degraded(MD),and heavily degraded(HD)]of subalpine meadow in the Mount Wutai.The results showed that there were significant differences in the relative abundances of Actinobacteria,Bacteroidetes,Nitrospirae,and Parcubacteria among the four subalpine grasslands with different degradation degrees(P<0.05).Compared with that in ND,the degraded meadows increased the proportion of genes related to carbon metabolism,biosynthesis of amino acids,pyruvate metabolism,citric acid cycle,propanoate metabolism,butanoate metabolism,and fatty acid metabolism(P<0.05),indicating that the degradation of subalpine grassland changed the metabolic potential of energy metabolism and the nutrient cycle of the soil microbial community.Grassland degradation changed soil microbial taxonomic and functionalαdiversity,especially in MD and HD.Grassland degradation resulted in significant changes in the taxonomic and functional compositions of the microbial communities.The total nitrogen,pH,and soil organic carbon significantly affected the taxonomic and functional compositions of the microbial communities.Theβdiversity of the plant community was significantly correlated with the taxonomic and functionalβdiversity of the microbial community(P<0.05),indicating strong coupling.The results of this study revealed the changes and driving mechanisms of subsurface microbial taxonomic and functional diversity during grassland degradation,which can provide a theoretical basis for subalpine meadow protection and ecological restoration.
作者
罗正明
刘晋仙
胡砚秋
赫磊
周妍英
郑庆荣
柴宝峰
LUO Zheng-ming;LIU Jin-xian;HU Yan-qiu;HE Lei;ZHOU Yan-ying;ZHENG Qing-rong;CHAI Bao-feng(Department of Geography,Xinzhou Normal University,Xinzhou 034003,China;Shanxi Key Laboratory of Ecological Restoration for Loess Plateau,Institute of Loess Plateau,Shanxi University,Taiyuan 030006,China;Shanxi Forestry and Grassland General Engineering Station,Taiyuan 030006,China;Department of Biology,Xinzhou Normal University,Xinzhou 034003,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2023年第5期2918-2927,共10页
Environmental Science
基金
国家自然科学基金项目(31801962)
山西省高等学校人文社会科学重点研究基地项目(2022J027)
山西省高等学校科技创新项目(2021L465)。
关键词
功能多样性
草地退化
亚高山草甸
宏基因组测序
土壤微生物
functional diversity
grassland degradation
subalpine meadow
metagenomic sequencing
soil microbial community
