Abstract: Soil multifunctionality is a key factor to maintain the stability of desert steppe ecosystem. The study of its dynamic changes has important scientific value for revealing the mechanism of regional ecological restoration. To investigate the dynamics of soil multifunctionality and its linkages with biodiversity during post-abandonment succession in a desert steppe ecosystem， this study targeted the desert grasslands in northwestern Wuchuan County， Inner Mongolia. Employing a space-for-time substitution approach， we analyzed soil single and multifunctionality across chrono sequences of abandoned croplands （5-， 15-， and 20-year post-abandonment） and natural grassland， and evaluated their relationships with plant and microbial diversity. The results indicate that， apart from the moisture regulation function， neither the nutrient cycling function， production function， nor soil multifunctionality had recovered to the level of natural grasslands after 20 years of abandonment. Multiple regression indicated that plant diversity predominantly governed soil water regulation， soil multifunctionality and nutrient cycling during restoration. In contrast， production function emerged as a synergistic outcome of plant diversity and fungal diversity. These results provide scientific references for rational grassland utilization and construction， and developing effective grassland management strategies to enhance soil functionality in desert grasslands.

Key words: Desert grassland, Abandoned cultivation succession, Multifunctionality of soil, Biodiversity

摘要： 土壤多功能性作为维持荒漠草原生态系统稳定的关键因子，其动态变化研究对揭示区域生态恢复机制具有重要科学价值。为探究荒漠草原弃耕演替过程中土壤多功能性的变化规律及其与生物多样性的关系，本研究以内蒙古呼和浩特市武川县西北部荒漠草原为研究对象，采用空间代替时间的方法，选取弃耕5年、15年和20年的样地及天然草地，分析了不同弃耕年限下土壤单一功能、多功能性的变化趋势及其与植物和微生物生物多样性的相互关系。结果表明：除水分调节功能，养分循环功能、生产功能、土壤多功能性均未在弃耕20年时恢复至天然草地水平。多元回归分析表明，弃耕恢复过程中土壤的水分调节功能、养分循环功能以及土壤多功能性主要受到植物多样性的调节，而生产功能主要受植物多样性真菌多样性的共同调节。研究结果为草地合理利用与建设，提升荒漠草原土壤功能有效措施的提出提供科学的参考依据。

关键词: 荒漠草原, 弃耕演替, 土壤多功能性, 生物多样性