武功山草甸土壤微生物学特性的变异及影响因素

发布时间：2018-07-15 20:14

【摘要】：草甸是分布广泛的陆地生态系统类型之一,对全球变化极为敏感。江西武功山草甸是亚热带山地草甸的典型代表,在华东植被垂直带谱中具有典型性和特殊性。本研究以探讨武功山山地草甸生态系统不同海拔高度及退化程度土壤微生物学特性为初始目的和切入点,深入分析基于海拔高度及草甸退化程度等外部因子所构建的土壤微生物学特性变异规律,对土壤微生物学特性产生影响的内部环境因子进行综合研究,包括土壤酶活性、土壤理化性质等变异特征,探讨土壤环境因子与微生物学特征因子之间的关联特性,以此为基础对山地草甸土壤综合质量变异特征进行评价,并对山地草甸植被生物量变异特征进行研究,也对生物量与土壤生物学特性、理化特性、酶活性的互作效应进行阐述,从多角度来阐述山地草甸土壤微生物学特性的变异及其影响因素。为开展退化山地草甸生态修复工作及开展区域可持续发展工作提供理论指导,同时,可以为亚热带山地草甸生态系统的管理提供参考依据。主要结论如下:(1)研究区的细菌有42个门,110个纲,165个目,189个科,200个属;优势细菌门为酸杆菌门(Acidobacteria)、变形菌门(Proteobacteria)和泉古菌门(Crenarchaeota);真菌有123个门,238个纲,259个目,302个科,359个属。优势真菌门为担子菌门(Basidiomycota)、子囊菌门(Ascomycota)、球囊菌门(Glomeromycota)。在不同海拔范围,土壤微生物分布的变异特征主要来自于高海拔区域的1900 m或1800 mm范围,而不同退化程度山地草甸土壤微生物分布变异特征主要来源于重度草甸退化区域。(2)武功山不同海拔高度及不同退化程度草甸土壤水源涵养功能存在变异。在不同海拔高度水源涵养能力表现为1600 m1800 m 1700 m1900 m。随草甸退化程度的增强,土壤的水源涵养能力减弱,其变异性表现为未退化轻度退化中度退化重度退化。土壤渗透性在1600 m-1800m范围,随着海拔升高土壤渗透性逐渐降低,而在高海拔的1900 m范围又渗透性提高。随着草甸退化的增强,土壤渗透性逐渐降低。通用经验模型能更好的拟合本研究区的土壤渗透过程。土壤pH变异特征表现为随海拔升高而增加,随草甸退化程度的增加,pH值减小;土壤有机质在不同海拔及退化草甸区域的变异性不显著;土壤全钾含量随海拔升高而增加,全磷和速效磷含量随草甸退化程度的增加而增加;速效硫含量随海拔升高而减小,随草甸退化程度的增强而增加;速效锰含量随海拔升高和草甸退化程度的增强而呈减少的变异趋势。(3) 土壤容重、平均入渗率、pH、全钾、速效氮、速效磷、蔗糖酶是影响武功山山地草甸土壤微生物学特性变异的关键环境因子。土壤平均渗透率、pH、速效氮、速效磷、真菌OTUs数量等5个指标,可以作为评价武功山不同旅游干扰程度草甸土壤质量综合指数(SQI)的最小数据集(MDS),其中,土壤平均渗透率、pH是进行土壤质量评价的核心因子。不同海拔高度山地草甸土壤质量综合表现为1600 m1700 m1900m1800 m,土壤质量指数分别为0.705、0.683、0.539、0.612 ;不同草甸退化程度山地草甸土壤质量综合表现为CKLDMDSD, 土壤质量指数分别为0.612、0.493、0.448、0.416。(4)随着海拔升高和草甸退化程度的加重,草甸单位面积生物量总体呈减少趋势。细菌多样性指数与叶生物量有显著的正相关性,而细菌OUTs数量则与叶生物量比和根生物量比分别正负相关,蓝细菌门、广古菌门、硝化螺旋菌门与叶生物量则成一定的负相关性。球囊菌门与植被总生物量正相关,壶菌门与叶生物量负相关。土壤过氧化氢酶与植被根生物量及总生物量均呈正相关性,而蔗糖酶与叶生物量有负相关性。土壤全钾、速效磷与植被叶生物量负相关关系。
[Abstract]:Meadow, one of the widely distributed terrestrial ecosystem types, is extremely sensitive to global change. The meadow of Wugong Mountain, Jiangxi is a typical representative of the subtropical mountain meadow, and is typical and special in the vertical band spectrum of the vegetation in East China. This study is to discuss the soil meadow of the meadow ecological system in Wugong Mountain mountains at different altitudes and degradation degrees. The characteristics of physicology are the initial purpose and the breakthrough point. The variation of soil microbiological characteristics based on the altitude and the degree of meadow degradation is deeply analyzed, and the internal environmental factors that affect the soil microbiological characteristics are studied comprehensively, including the soil enzyme activity, the soil physical and chemical properties and so on. The relationship between the soil environmental factors and the microbiological characteristic factors is based on the evaluation of the variation characteristics of the soil comprehensive quality in the meadow, and the variation characteristics of the vegetation biomass in the meadow, and the interaction effect of the biomass and soil biological characteristics, the physicochemical properties and the enzyme activity. The variation and influencing factors of the soil microbiological characteristics of the meadow in the mountain meadow were expounded. The theoretical guidance for the ecological restoration and regional sustainable development of the degraded alpine meadow was provided. At the same time, it could provide a reference for the management of the subtropical meadow ecosystem. The main conclusions are as follows: (1) there are 42 bacteria in the study area. Doors, 110 classes, 165 orders, 189 families and 200 genera; dominant bacteria gates are Acidobacteria, Proteobacteria and Crenarchaeota; fungi have 123 doors, 238 classes, 259 orders, 302 families, 359 genera. The dominant fungi gate is basidiomycetes (Basidiomycota), Ascomycota, and balloon (Glomero). Mycota). At different altitudes, the variation characteristics of soil microbial distribution mainly come from 1900 m or 1800 mm in high altitude regions, and the distribution and variation of soil microbes in Different Degraded Mountain Meadows mainly originate in the severe meadow degraded areas. (2) Wugong Mountain is different from altitude and different degraded meadow soil water sources. The water conservation ability at different altitudes is 1600 M1800 m 1700 m1900 M. with the increase of Meadow Degradation, the water conservation ability of soil is weakened, and the variability of the soil water conservation ability is not degraded mild and moderate degeneration and severe degradation. Soil permeability is in the range of 1600 m-1800m, and the soil permeability increases with elevation. Permeability gradually decreased, and permeability increased at 1900 m range in high altitude. With the increase of Meadow Degradation, soil permeability decreased gradually. The general experience model could better fit the soil infiltration process in this study area. The characteristics of pH variation in soil increased with the elevation of altitude, with the increase of the degree of Meadow Degradation, the decrease of pH value; The variation of organic matter in different altitudes and degraded meadow areas was not significant; the total potassium content of soil increased with the elevation of altitude. The content of total phosphorus and available phosphorus increased with the increase of Meadow Degradation; the content of quick acting sulfur decreased with the elevation of altitude, increased with the degree of meadow degradation; the content of available manganese increased with the elevation of the altitude and the meadow degradation. (3) soil bulk density, average infiltration rate, pH, total potassium, available nitrogen, available phosphorus, and invertase are the key environmental factors affecting the variation of soil microbiological characteristics in Wugong Mountain mountain meadow. The average soil permeability, pH, available nitrogen, available phosphorus, and the number of fungi OTUs can be used as the evaluation of Wugong Mountain. The minimum data set (MDS) of the soil mass index (SQI) of the meadow soil mass index (SQI) of different degree of tourism disturbance, among which the soil average permeability, and the core factor of soil quality evaluation, the soil quality of the meadow at different altitudes is 1600 m1700 m1900m1800 m, the soil quality index is 0.705,0.683,0.539,0.612, and the different grass is different. The soil quality of the meadow meadow was CKLDMDSD, and the soil mass index was 0.612,0.493,0.448,0.416. (4), respectively, with the increase of altitude and the degree of Meadow Degradation, the biomass per unit area of meadow decreased. The bacterial diversity index had a significant positive correlation with the Ye Sheng biomass, while the number of bacteria OUTs was the same. There was a negative correlation between the leaf biomass ratio and the root biomass ratio. The cyanobacteria gate, the palaeobacteria door, the nitrification spiral gate and the leaf biomass were negatively correlated. The saccule doors were positively related to the total biomass of the vegetation, and the phylum phyllocultum was negatively correlated with the leaf biomass, and the soil catalase was positively correlated with the biomass and total biomass of the plant root. Invertase was negatively correlated with leaf biomass. Soil total potassium and available phosphorus were negatively correlated with biomass of vegetation leaves.
【学位授予单位】：江西农业大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：S812.2

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