Plant secondary succession has been explored extensively in restoring degraded grasslands in semiarid or dry environments. However, the dynamics of soil microbial communities and their interactions with plant succession following restoration efforts remain understudied, particularly in alpine ecosystems. This study investigates the interplay between soil properties, plant communities, and microbial populations across a chronosequence of grassland restoration on the Qinghai–Tibet Plateau in China. We examined five succession stages representing artificial grasslands of varying recovery durations from 0 to 19. We characterized soil microbial compositions using high-throughput sequencing, enzymatic activity assessments, and biomass analyses. Our findings reveal distinct plant and microbial secondary succession patterns, marked by increased soil organic carbon, total phosphorus, and NH₄⁺-N contents. Soil microbial biomass, enzymatic activities, and microbial community diversity increased as recovery time progressed, attributed to increased plant aboveground biomass, cover, and diversity. The observed patterns in biomass and diversity dynamics of plant, bacterial, and fungal communities suggest parallel plant and fungal succession occurrences. Indicators of bacterial and fungal communities, including biomass, enzymatic activities, and community composition, exhibited sensitivity to variations in plant biomass and diversity. Fungal succession, in particular, exhibited susceptibility to changes in the soil C: N ratio. Our results underscore the significant roles of plant biomass, cover, and diversity in shaping microbial community composition attributed to vegetation-induced alterations in soil nutrients and soil microclimates. This study contributes valuable insights into the intricate relationships driving secondary succession in alpine grassland restoration.

The establishment of artificial grasslands is a highly effective strategy for the rapid restoration of degraded grasslands. To investigate the dynamics of biomass production and plant diversity—two critical objectives of grassland restoration—and their relationship during the early stages of artificial grassland establishment, we conducted an experiment in Menyuan County, located in the northeastern region of the Qinghai-Tibet Plateau. The experiment involved sowing different combinations of species (one, three, six, and nine species). Using data collected over three years (2021–2023), we found that biomass production generally increased over time. Specifically, in the second year, biomass production exhibited a unimodal relationship with the number of sown species, while in the third year, it increased linearly with the number of sown species. Plant diversity, which includes both sown and naturally occurring species, initially increased with the number of sown species in the first year but decreased in mixed sown plots in the third year. In the first year, biomass production was not correlated with plant diversity, whereas in the second and third years, biomass production decreased as plant diversity increased. This pattern was primarily driven by the accelerated growth of Gramineae. These results highlight the complex dynamics between biomass production and plant diversity during the early stages of artificial alpine grassland establishment. Our findings suggest that a trade-off between biomass and biodiversity should be carefully considered when designing restoration strategies, as achieving both high productivity and biodiversity may require a more nuanced approach.