3.5 Functional responses of bacterial community to grassland degradation
PICRUSt analysis was conducted to investigate variation in bacterial community functional structure in the course of grassland degradation. Bacterial functional gene diversity in highly degraded grassland was higher than that in slightly degraded grasslands (Table S4,P < 0.05) . In addition, the KO gene numbers of each OTU increased significantly with the progression of degradation, and were negatively correlated with soil nutrient (OM, TN, and TP) contents(Table S5, P < 0.05) . The results indicated that bacterial communities in degraded grassland conditions and relatively poor nutrient conditions would harbor relatively high amounts of genetic information. In addition, genetic information harbored by species increased with an increase in ses.MNTD (Figure 5,P < 0.05) , indicating that phylogenetic dispersion in community assembly under grassland degradation would lead to more functional genes, which could facilitate better adaptation by communities to resource scarcity.