Soil and vegetation characteristics during the formation of typical degraded grassland.

To understand the formation process of typical poisonous plant degraded grassland, we studied the cha-racteristics of vegetation and soil during the gradual expansion of into the native grassland of Qinghai-Tibet Plateau. The results showed that population density, plant height, coverage, and biomass of increased during the formation of degraded grassland. In comparison with native grassland, the degraded grassland had higher total aboveground biomass (113.9%), soil total nitrogen concentration (61.0%), NH-N (77.9%), organic carbon concentration (45.3%), available phosphorus concentration (78.8%) as well as soil microbial biomass carbon (42.1%) and nitrogen (47.4%), but lower NO-N (40.1%) and species richness (28.5%) and aboveground biomass (45.7%) of other species beyond . The extremely strong abilities of interspecific inhibition and morphological plasticity of , as well as efficient nutrient accumulation and utilization were the keys to its successful expansion, which facilitated the formation of typical degraded grassland.