Responses of microbial community composition and CAZymes encoding gene enrichment in ensiled <i>Elymus nutans</i> to altitudinal gradients in alpine region

The fermentation quality of <i>Elymus nutans</i> silage was getting better with the increase of altitude in the Qinghai-Tibetan Plateau. The abundance of hosts carrying carbohydrate-active enzymes genes and key enzyme genes related to organic acid production increased with increasing altitude during the later stages of fermentation. <i>Lactiplantibacillus</i> and <i>Pediococcus</i> were the core microorganisms responsible for both polysaccharide hydrolysis and silage fermentation in the late stage of ensiling. This study provided insights on the influence of different altitudes on the composition and function of silage microbiome in the Qinghai-Tibetan Plateau, and provided a reference approach for improving the quality and controllability of silage production in high altitude areas of the Qinghai-Tibetan Plateau.