关键词: 亚热带, 植被恢复, 球囊霉素, 微生物特性, 土壤有机碳

Abstract: Abstract Aims To elucidate the dynamic changes of glomalin-related soil protein (GRSP) during subtropical vegetation restoration and to explore the effects of soil physicochemical properties and microbial characteristics on GRSP, this study aimed to provide a scientific basis for improving soil ecological functions in subtropical ecosystems. Methods Five vegetation restoration stages (herb, shrub, early forest, middle forest, and late forest) in the subtropical region of China were selected. Soil samples were collected to systematically determine soil physicochemical properties, GRSP (including total GRSP, T-GRSP, and easily extractable GRSP, EE-GRSP), soil microbial biomass, and microbial community composition. Random forest and partial least squares path modeling were employed to identify the main factors influencing T-GRSP and EE-GRSP. Important findings Vegetation restoration significantly promoted the accumulation of GRSP. The contents of T-GRSP and EE-GRSP increased from 1.73±0.19 and 0.64±0.03 g·kg-1 at the herb stage to 7.86±0.46 and 2.07±0.06 g·kg-1 at the late forest stage, respectively. However, the contribution of GRSP to soil organic carbon (SOC) decreased along the restoration gradient. The ratio of T-GRSP/SOC declined from 13.24±2.39% to 5.28±0.20%, and EE-GRSP/SOC decreased from 4.98±0.92% to 1.40±0.06%, with significantly higher values observed at the herb stage compared to other stages. SOC, pH, total nitrogen, total phosphorus, microbial biomass carbon, gram-positive bacteria, and the fungi-to-bacteria ratio were identified as key drivers of GRSP accumulation.

Key words: subtropical, vegetation restoration, glomalin, microbial characteristics, soil organic carbon