摘要
固氮微生物作为土壤中重要的功能微生物群之一,其变化与土地利用方式密切相关.以林地(WD,对照)、幼龄茶园(YT)、成龄茶园(AT)及高海拔茶园(WD)为研究对象,采用高通量测序技术,探究4种样地土壤固氮菌多样性及群落结构,并对土壤理化性质与固氮菌多样性和群落结构的关系进行相关性分析和冗余分析(RDA).结果显示,与林地土壤相比,幼龄茶园固氮菌Alpha多样性有所降低,其中Shannon指数显著降低(P <0.05),而林地、成龄茶园和高海拔茶园之间固氮菌Alpha多样性差异不显著(P> 0.05).从4类样地土壤样品中共检测到固氮菌27个门49个纲93个目169个科337个属,其中变形菌门(Proteobacteria)和慢生根瘤菌属(Bradyrhizobium)是各样地土壤固氮菌的绝对优势菌群,其相对丰度分别为88.54%-90.17%和21.25%-61.57%.结合Venn图和非度量多维尺度(NMDS)可看出,植茶年限明显影响土壤固氮菌微生物群落结构,林地和幼龄茶园土壤固氮微生物群落结构相似性较近,林地和成龄茶园固氮微生物落结构群落结构相似性较远. LEfSe分析表明,幼龄茶园土壤中差异物种数量最低,高海拔茶园土壤中差异物种数量最多.相关分析和冗余分析结果表明,土壤有机质、铵态氮和速效磷是影响土壤固氮菌群落丰度和多样性的主要土壤因子,但土壤性质对土壤固氮微生物群落结构变化的解释度较低(分别仅为22.9%和42.0%).本研究表明林地转变为茶园后,幼龄茶园固氮菌多样性明显降低,而成龄茶园土壤固氮菌多样性得以恢复,但土壤固氮菌群落结构发生明显变化,涵盖的土壤理化性质指标并不能完全解释固氮微生物群落的变异,还需结合更多因素进行进一步探讨.(图8表2参43)
Nitrogen-fixing bacteria are among the most important functional microorganisms in the soil, and changes in the soil nitrogen-fixing bacteria community and its diversity is usually related to land-use. We selected forestland(WD, CK), young tea garden(YT), mature tea garden(MT), and high elevation tea garden(HT) soils in Fujian province as study sites, and the diversity and structure of the nitrogen-fixing bacteria were then studied by high-throughput sequencing technology. Pearson’s correlation analysis and redundancy analysis(RDA) were used to examine the soil physicochemical factors driving the community structure and diversity of the soil nitrogen-fixing bacteria. The results showed that compared with the forestland, the soil nitrogen-fixing bacterial diversity in the young garden was remarkably reduced. Moreover, Simpson’s indices significantly decreased(P < 0.05), compared to the forestland. A total of 27 phyla, 49 classes, 93 orders, 169 families, and 337 genera of nitrogen-fixing bacteria were detected from the soil samples. Proteobacteria was the dominant phylum, and Bradyrhizobium was the dominant genus in all soil samples;the relative abundances were 88.54%-90.17% and 21.25%-61.57%, respectively. The results of the Venn diagram and non-metric multidimensional scaling analysis(NMDS) showed that the tea plantation age played a vital role in driving changes in the soil nitrogen-fixing bacteria community structure. The nitrogen-fixing bacteria communities in forestland and the young tea garden had a similar composition, whereas the nitrogen-fixing bacteria communities in the forestland and mature tea garden were different. Results from the linear discriminant analysis effect size pipeline(LEfSe) analysis showed that the number of distinct indicator species was the highest in high elevation tea garden soil and the lowest in young tea garden soil. The results of Pearson’s correlation analysis and redundancy analysis(RDA) showed that soil organic matter, NH4+-N, and available phosphorus were the main factors affecting the abundance and diversity of the soil nitrogen-fixing bacteria community, but the cumulative explanation of the first two axes was only 22.9% and 42.0% of the environmental variables. In conclusion, the soil nitrogen-fixing bacterial diversity was significantly reduced in the change from forest to tea garden, then the soil bacterial diversity improved as the tea plantation age increased. However, the nitrogen-fixing bacteria communities varied remarkably. The studied environmental variables could not fully explain the variation in the nitrogenfixing microbial communities, and further investigation into the effect of converting forest into tea garden on soil nitrogen-fixing bacteria should examine more factors.
作者
陈玉真
王峰
吴志丹
张文锦
翁伯琦
尤志明
CHEN Yuzhen;WANG Feng;WU Zhidan;ZHANG Wenjin;WENG Boqi;YOU Zhiming(Tea Research Institute,Fujian Academy of Agricultural Sciences,Fuzhou 350013,China;Scientific Observing and Experimental Station of Tea Tree and Oolong Tea Processes in Fujian,Ministry of Agriculture,Fu’an 355015,China;Fujian Provincial Key Laboratory of Agro-Ecological Processes in Hilly Red Soil,Fuzhou 350013,China)
出处
《应用与环境生物学报》
CAS
CSCD
北大核心
2020年第5期1096-1106,共11页
Chinese Journal of Applied and Environmental Biology
基金
国家重点研发计划项目(2016YFD0200903)
福建省科技厅公益类科研项目(2018R1012-2,2018R1012-1)
中央引导地方科技发展专项(2020L3030)
福建省科技重大专项(2017NZ0002)
福建省农业科学院科技创新团队项目(STIT2017-1-3,STIT2017-3-8)资助。
关键词
林地开垦
高通量测序
固氮菌
群落结构
多样性
影响因子
reclamation of forestland
high throughput sequencing
soil nitrogen-fixing bacterial
community structure
diversity
impact factor
