干旱对土壤微生物的影响及其与碳动态的关系  

Effects of Drought on Soil Microorganism and Its Relationship with Carbon Dynamics

作　　者：黎雪 张坐省[1] 党占平[1] 王灿[1] 

机构地区：[1]杨凌职业技术学院,陕西杨凌712100

出　　处：《山西农业科学》2018年第3期402-406,共5页Journal of Shanxi Agricultural Sciences

基　　金：陕西省教育厅重点实验室项目(17JS142)

摘　　要：干旱是影响土壤微生物变化及其土壤碳动力学特征的重要因素之一,因此,探讨不同干旱强度下土壤微生物的变化对揭示土壤陆地生态系统碳循环具有重要意义。基于此,研究着眼于全球尺度,采用整合分析方法研究不同干旱水平、不同干旱时间以及不同植被类型下,土壤微生物群落的变化特征及其与土壤碳的关系。结果表明,在轻度干旱水平上(0~35%),微生物生物量增加27.95%,细菌降低0.44%,真菌增加0.67%;在中度干旱水平上(36%~70%),微生物生物量下降4.11%,细菌降低5.21%,真菌增加8.57%;在重度干旱水平上(71%~100%),微生物生物量下降14.68%,细菌降低3.85%,真菌降低4.99%。对于总体微生物而言,相较于灌木林、乔木林、草地等土地利用方式,农田干旱使总微生物量显著降低22.93%。干旱时间对土壤微生物生物量的影响程度也不同,尤其是短期干旱(0~30 d),其土壤微生物显著降低,降低了11.94%。相关性分析表明,在干旱情况下,土壤微生物与土壤碳的动态变化呈现出显著正相关。Drought is one of the important factors affecting soil microbe and soil carbon dynamics,and exploring the changes of soil microbe under different drought intensities are of great significances for revealing soil carbon cycle in terrestrial ecosystems.In this study,a meta-analysis to synthesize the responses of soil microbes to drought and their implications for soil carbon dynamics（soil carbon and respiration）was conducted.The results showed that,at the light drought level（0-35%）,soil microbial biomass and fungi were increased by 27.95% and 0.67%,respectively,but soil bacteria was decreased by 0.44%.At the moderate drought level（36%-70%）,soil microbial biomass and bacteria were declined by 4.11% and 5.21%,respectively,while the fungi were increased by 8.57%.At the heavy drought level（71%-100%）,soil microbial biomass,bacteria and fungi were decreased by 14.68%,3.85%,4.99%,respectively.With respect to vegetation types effects,soil total microbial biomass（microbial biomass＋bacteria ＋ fungi）were significantly decreased by 22.93% in farmland.Moreover,soil total microbial biomass responded differently to drought duration,particularly,in short drought（0-30 day）,soil total microbial biomass was significantly decreased by 11.94%.Furthermore,the responses of soil microbes to drought were significantly and positively correlated to the response of soil carbon dynamic.

关 键 词：干旱 土壤微生物 土壤碳变化 整合分析 全球尺度 

分 类 号：S154.3[农业科学—土壤学]