青藏高原高寒湿地退化过程中土壤微生物群落功能多样性特征

为给高寒湿地的退化监测和恢复治理提供科学理论依据，本试验在三江源黄河源区选取退化高寒湿地，采用空间代替时间的方法，选取不同退化阶段并利用常规实验室分析法和Biolog-Eco微平板法研究其土壤微生物群落结构及功能的变化特征。结果表明，高寒湿地、沼泽化草甸和退化草甸样地微生物群系相似性更高。不同退化程度的土壤微生物活性从高到低排序依次为：沼泽化草甸 > 退化草甸 > 湿地 > 重度退化草甸 > 退化草原。整个退化过程土壤微生物对酯类碳源代谢能力均为最强，在退化早期土壤微生物对酸类碳源的利用率较低。土壤微生物平均颜色变化率（Average well color development，AWCD）主要受到土壤全氮含量、土壤有机碳含量、全氮/全磷、植物盖度、土壤含水量和地下生物量的影响。

Functional Diversity of Soil Microbial Communities during Degradation of Alpine Wetlands in Qinghai-Tibet Plateau

In order to provide scientific basis for the restoration of wetland in the Qinghai-Tibet Plateau,the degraded alpine river wetlands were selected in the source area of the Yellow River in Sanjiangyuan,and the spatial replacement time was adopted to select the different wetland degradation stages. In our study,microbial community functional diversity of different stand types in the reverse succession of alpine wetlands was analyzed by conventional laboratory analysis and Biolog-Eco micro plate method. Our results showed that the microbial flora similarity of alpine wetland,swamp meadow and degraded meadow was higher than that of severely degraded meadow and degraded steppe. The order of soil microbial activity from high to low in the reverse succession of alpine wetlands was swamp meadow > degraded meadow > alpine wetland > severely degraded meadow > degraded grassland. During the degradation process,the soil microorganisms had the strongest metabolic capacity for ester carbon sources,and the soil microorganisms had a lower utilization of acid carbon sources in the early stages of degradation. In addition,the AWCD value of soil microorganisms were mainly affected by soil total nitrogen contents,soil organic carbon contents,total nitrogen vs total phosphorus,plant cover,soil water contents and underground biomass.