Effects of Reseeding and Fertilization on Bacterial Communities in Rhizosphere Soil of Alpine Degraded Grassland

Reseeding and fertilization are common ecological restoration measures in the Qinghai-Tibet Plateau Region for degraded grasslands，yet their impacts on rhizospheric bacterial communities remain unclear. This study utilized high-throughput sequencing technology to systematically investigate the characteristics of rhizospheric soil bacterial communities in degraded high-altitude grasslands managed with reseeding and fertilization. The results indicated a significant decrease in the Shannon and Simpson indices with fertilization treatment，while the reseeding + fertilization treatment exhibited the most pronounced impact on community structure. Actinomycetota，Pseudomonadota，and Acidobacteriota were the dominant phyla in the rhizosphere bacterial community. There was a decrease in network complexity and an increase in stability within bacterial communities with the reseeding，fertilization，and fertilization + reseeding treatments. The networks were predominantly characterized by positive correlations after fertilization，reseeding，and fertilization + reseeding treatments，involving key species like Pseudomonadota，Actinomycetota，and Acidobacteriota. Mantel tests revealed that soil total nitrogen（TN），total phosphorus（TP），available potassium（AK），and nitrate nitrogen（NO3--N）were the key environmental factors in driving bacterial community composition. The study of the rhizosphere soil bacterial community in alpine degraded grassland can provide a theoretical basis for tailored management strategies in the restoration of degraded high-altitude grasslands and lays a scientific foundation for their conservation. © 2024 Science Press. All rights reserved.