庞泉沟自然保护区森林土壤微生物群落结构特征

发布时间：2018-10-18 07:21

【摘要】：本文运用高通量测序和实时荧光定量PCR技术分析庞泉沟自然保护区沙棘(Hippophae rhamnoides)灌丛、锦鸡儿(Caragana jubata)灌丛、桦树(Betula platyphylla)林、辽东栎(Quercus wutaishansea)林、山杨(Populus davidiana)林和两个华北落叶松(Larix principis-rupprechtii)林的土壤微生物群落结构及细菌功能类群的丰度,同时测定了土壤过氧化氢酶、脲酶、蔗糖酶活性以及土壤环境因子,对各因子的变化规律及其之间的相关性进行了分析。旨在了解庞泉沟土壤细菌群落与环境因子和空间变量的生态关系,为了解微生物群落对环境条件变化的响应来预测环境的变化提供理论依据。其结果表明:1.五个阔叶林土壤环境因子与土壤酶的相关性分析,脲酶与铵态氮、有机质极显著正相关,与全氮、全碳显著正相关;蔗糖酶与全氮、全碳、全硫和有机质极显著正相关;过氧化氢酶与铵态氮极显著正相关。2.除了锦鸡儿样地的植物多样性在七月高,其他样地均五月高于七月。相关性分析,植物多样性与脲酶、全氮、全碳、硝态氮显著正相关。3.高通量测序表明,桦树林土壤细菌群落多样性和丰度高于华北落叶松林,真菌群落的丰度与之相反;高海拔落叶松林细菌群落多样性较低,而丰度较高,真菌群落则是丰度较低,多样性在高海拔落叶松林中最高,在桦树林中较低。阔叶林空间季节动态结果为,除了锦鸡儿灌丛样地的细菌丰度在四月高于其它月份,其它样地都在五月达到最高;细菌丰度季节变化整体趋势均为四、五月较高,而七、十月较低;沙棘灌丛在各样地中最低。细菌功能类群的丰度整体趋势与其一致。4.高通量测序表明,桦树林和两个华北落叶松林样地的土壤细菌群落结构具有一定差异,而真菌群落结构的差异较大,土壤理化性质对微生物群落的结构具有较大的影响。细菌和真菌群落结构与土壤碳氮比、全硫、pH、粒径、脲酶、蔗糖酶和过氧化氢酶活性紧密相关。阔叶林细菌优势类群丰度与环境因子相关性分析表明,细菌丰度与全碳、全硫、有机质、蔗糖酶紧密相关,蔗糖酶与α-变形菌纲、浮霉菌门、γ-变形菌纲极显著正相关;脲酶与浮霉菌门、α-变形菌纲显著正相关;过氧化氢酶与细菌极显著正相关。
[Abstract]:In this paper, high-throughput sequencing and real-time fluorescence quantitative PCR were used to analyze seabuckthorn (Hippophae rhamnoides) shrub, Caragana (Caragana jubata) shrub, birch (Betula platyphylla) forest and Quercus liaotungensis (Quercus wutaishansea) forest in Pang Quangou Nature Reserve. The soil microbial community structure and the abundance of bacterial functional groups in Populus (Populus davidiana) and two Larix principis-rupprechtii stands were determined. The activities of catalase, urease, sucrase and soil environmental factors were also determined. The variation law of each factor and its correlation are analyzed. The purpose of this study was to understand the ecological relationship between soil bacterial community and environmental factors and spatial variables in Pang Quangou, and to provide a theoretical basis for understanding the response of microbial communities to changes in environmental conditions in order to predict environmental changes. The results show that: 1. The correlation between soil environmental factors and soil enzymes in five broadleaved forests showed that urease was significantly positively correlated with ammonium nitrogen, organic matter and total nitrogen, total carbon, sucrase and total nitrogen, total carbon, total sulfur and organic matter, and that urease was significantly positively correlated with total nitrogen, total carbon, total sulfur and organic matter. Catalase was positively correlated with ammonium nitrogen. 2. The plant diversity of Caragana samples was higher in July than in May. Correlation analysis showed that plant diversity was positively correlated with urease, total nitrogen, total carbon and nitrate nitrogen. High throughput sequencing showed that the diversity and abundance of soil bacterial community in birch forest was higher than that in North China larch forest, but the abundance of fungal community was opposite, and the diversity of bacterial community was lower and the abundance was higher in larch forest at high altitude. The diversity of fungal community was the highest in the larch forest at high altitude and the lowest in the birch forest. The results of spatial seasonal dynamics of broad-leaved forest were as follows: except that the bacterial abundance of Caragana thickets was higher in April than in other months, the bacterial abundance of other plots reached the highest in May, and the overall trend of seasonal variation of bacterial abundance was in April, higher in May, and higher in 7. October was lower; seabuckthorn thickets were the lowest in all lands. The overall trend of the abundance of bacterial functional groups is consistent with that of. 4. 4. High throughput sequencing showed that there were some differences in soil bacterial community structure between birch forest and two larch stands in North China, but there was great difference in fungal community structure, and soil physical and chemical properties had great influence on the structure of microbial community. The community structure of bacteria and fungi was closely related to soil C / N ratio, total sulfur, pH, particle size, urease, sucrase and catalase activity. The results showed that bacterial abundance was closely related to total carbon, total sulfur, organic matter and sucrase, while sucrase was positively correlated with 伪 -Proteus, phylum floatula and 纬 -Proteus. Urease was positively correlated with the phylum, 伪 -Proteus, and catalase was positively correlated with bacteria.
【学位授予单位】：山西大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S714.3

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