【作者】 金裕华；

【导师】 阮宏华；

【作者基本信息】 南京林业大学 ， 生态学， 2012， 博士

【摘要】 本文以中国福建省武夷山国家自然保护区为实验地，选择不同海拔高度的4种主要植被类型：中亚热带常绿阔叶林(500m)、针叶林(1150m)、亚高山矮林(1750m)和高山草甸(2150m)为研究样地，从土壤微生物数量分布特征、土壤微生物碳源利用特征和土壤酶活性特征3方面研究了武夷山自然保护区沿海拔梯度变化典型植被带土壤微生物多样性的变化特征。从生物地理学的角度比较了沿海拔梯度变化各样地土壤微生物多样性分布规律，并就环境因子沿海拔高度的变化对土壤微生物群落多样性的影响进行了研究，阐述了气候、土壤和植物对土壤微生物分布的影响。主要研究结果如下：1、随海拔高度的上升，土壤微生物各类群数量分布发生了明显的变化，土壤微生物真菌数量随海拔升高而降低，土壤放线菌数量随海拔升高而升高(除了常绿阔叶林)，土壤细菌和纤维素分解菌数量随海拔升高而增加(除了亚高山矮林)，固氮细菌和氨化细菌随海拔的升高而降低(除了高山草甸)，硝化细菌海拔趋势不明显，高山草甸土壤硝化细菌极少很难检测出。土壤微生物各类群季节变化显著，峰值主要出现在春季、夏季和秋季，冬季最少。随海拔梯度升高，土壤细菌所占比例逐渐升高，土壤真菌比例逐渐降低，土壤微生物各类群数量与土壤理化性质的相关性逐渐降低。2、随海拔高度的上升，总体上各样地土壤微生物AWCD值和功能多样性指数大小顺序为：高山草甸>针叶林>常绿阔叶林≈亚高山矮林，不同季节和不同土层各样地土壤微生物AWCD值和功能多样性指数的大小顺序随之改变。各样地碳源利用图谱不同，林地与草地碳源利用图谱差异较大，同一样地碳源利用图谱季节变化明显。微生物功能多样性受土壤养分、土壤温湿度、pH、细根生物量和凋落物的影响，且不同季节这些因素对微生物多样性的贡献不同，总体来看土壤温度是对土壤微生物多样性变化贡献最大的因素3、随海拔高度的上升，土壤酶活性总体上是升高的(除了多酚氧化酶)。各样地土壤脲酶、蔗糖酶、酸性磷酸酶、过氧化氢酶和多酚氧化酶活性海拔差异显著；各样地土壤酸性磷酸酶、多酚氧化酶和蔗糖酶活性季节差异显著；各样地脲酶、过氧化氢酶活性季节差异不显著；土壤酶活性随土层加深而降低。武夷山各样地土壤酶活性与土壤养分、温度、湿度、土壤微生物数量、活性和多样性指数密切相关，各种酶活性间密切相关。更多还原

【Abstract】 We examined the soil microbial diversity by measuring the amount of soil microbes(bacteria, fungi, actinomucetes) and soil microbial major physiological group (nitrogen fixingbacteria, cellulose decomposing microbes, nitrifying bacteria and ammonifying bacteria) and theactivities of four soil enzymes (urease, sucrase, acidic phosphatase, catalase and polyphenoloxidase) at four typical vegetations along elevation i.e. evergreen broadleaf forest (EBF) at500m above sea level (asl), coniferous forest (CF) at1150m asl, sub-alpine dwarf forest (SDF) at1750m asl and alpine meadow (AM) at2150m asl, respectively, in the natural reserve of theWuyi Mountains in Fujian Province, China. We studied the distribution of soil microbialdiversity along elevation and the microbial effect of environmental changes along altitude fromthe point of view of the biogeography, and stated the relationship of soil microbial diversity withsoil, environment and vegetation along elevation. The major findings are as following:1. The amount of microbes altered along an elevation gradient. The amount of fungiincreased with altitude, the amount of actinomucetes increased with altitude (except EBF), theamount of bacteria and cellulose decomposing microbes increased with altitude (except SDF),the amount of nitrogen fixing bacteria and ammonifying bacteria decreased with altitude (exceptAM), the amount of nitrifying bacteria was very little. We did not find nitrifying bacteria at AM.The amount of microbes altered with seasons, and the peaks of microbes were in spring, summerand autumn, the bottoms of microbes were in winter. The ratio of soil bacteria increased withaltitude, and the ratio of fungi decreased with altitude. The degree of correlation of the amountof microbes with physical and chemical properties of soils receded with altitude.2. The AWCD of soil microbes and microbial functional diversity increased with altitude,with the order of AM>CF>EBF≈SDF, and the order changed with season and soil depth.Sole-carbon-source utilization profiles of soil microbial community were different betweendifferent sites and seasons, and pasture soil and forest soil had distinct differences of microbialcommunity carbon utilization profile. Micobial functional diversity at the four sites correlatedwith physical and chemical properties of soils, fine root biomass, and litter. Generally, soiltemperature was the most factors for micobial functional diversity.3. The activity of soil enzymes distinctly altered with elevation. The activity of soilenzymes increased with altitude (except polyphenol oxidase). The seasonal difference of theactivity of sucrase, acidic phosphatase and polyphenol oxidase were distinct, and that of ureaseand catalase were not significant. The activity of soil enzymes also decreased with soil depth.The activity of soil enzymes were highly correlated with physical and chemical properties ofsoils, soil temperature and soil moisture and, microbial diversity更多还原