近50 a来随着中国西北干旱地区人口数量的急剧增加，荒漠绿洲边缘农田和林地呈不断向沙漠扩张的趋势。目前关于荒漠绿洲扩张区土壤微生物群落演替和多功能性的变化规律研究还相对有限。本研究以河西走廊张掖绿洲扩张区域开垦和种植5 a、10 a、20 a、30 a农田和梭梭林（Haloxylon ammodendron）为研究对象，对0~20 cm土壤理化性质（土壤养分、pH、电导率、含水量）、土壤酶（碳、氮、磷酶）和土壤微生物（细菌和真菌：16S rRNA基因和ITS区域进行扩增子测序）进行取样分析，阐明农田和人工林地土壤细菌和真菌群落组成、结构、多样性和多功能性演变规律以及土壤多功能性与土壤微生物之间的潜在关系。结果表明：开垦30 a，农田土壤多功能性呈现先增长后降低的趋势，在开垦10 a时达到最高，20 a开始显著下降（P<0.05）；而梭梭林土壤多功能性随种植年限增加而增加，多功能性在30 a达到最大。对于农田，土壤真菌群落比细菌群落变化更为显著，其中土壤多功能性与真菌群落病原体呈显著负相关（r=-0.655，P<0.01），而与α多样性（r=0.508，P<0.05）和网络复杂性均呈显著正相关（r=0.645，P<0.05），主成分分析表明土壤真菌群落病原体可作为农田土壤多功能性变化的主要影响因素；对于梭梭林，细菌群落对土壤多功能性变化的贡献更强，多功能性与α多样性（r=0.546，P<0.001）和网络复杂性均呈显著正相关（r=0.542，P<0.001），土壤细菌群落α多样性和结构复杂性可作为梭梭林土壤多功能性关键影响因素。研究结果可为荒漠绿洲扩张区农田和林地土壤健康管理提供数据支持和科学依据。

Over the past 50 years, the population in the arid regions of Northwest China has rapidly increased, accompanied by the expansion of farmland and shrubland at the edge of desert oases. However, few studies have examined the succession and multifunctionality of soil microbial communities in the desert oasis expansion area. This study aimed to elucidate the ecological mechanisms underlying soil microbiome evolution and ecosystem functioning in arid land reclamation systems. We systematically investigated the spatiotemporal dynamics of soil microbial communities (bacteria and fungi: 16S ribosomal ribonucleic acid and internal transcribed spacer amplicon sequencing) and their functional relationships with the physicochemical properties of soil (nutrients, pH, electrical conductivity, moisture), enzymatic activities (C-, N-, P-cycling), and multifunctionality across a chronosequence (5-30 years) of cultivated farmlands and Haloxylon ammodendron plantations in the Zhangye oasis expansion zone of Hexi Corridor. The results indicated that over a reclamation period of 30 years, the multifunctionality of farmland soil first increased then decreased, reaching a maximum value at 10 years and exhibiting a significantly decreased value at 20 years (P<0.05). Conversely, the soil multifunctionality of Haloxylon ammodendron plantations increased with time, reaching its maximum value at 30 years. In the farmland, the fungal community changed more significantly than the bacterial community. Soil multifunctionality was significantly negatively correlated with relative abundance of pathotrophic fungi in the community (r=-0.655, P<0.01) but positively correlated with α-diversity (r=0.508, P<0.05) and network complexity (r=0.645, P<0.05). Principal component analysis identified fungal pathogens as the primary factor influencing farmland soil multifunctionality. The contribution of the bacterial community to changes in soil multifunctionality was stronger in shrubland than in farmland. Multifunctionality was significantly positively correlated with both α-diversity (r=0.546, P<0.001) and network complexity of the bacterial community (r=0.542, P<0.001), and these two were the primary factors influencing shrubland soil multifunctionality. The results of this study provide a scientific basis for the sustainable development of farmland and shrubland and the management of soil health in desert oasis expansion zones.