Effects of grassland vegetation restorations on poisonous plants in alpine meadow

In order to verify effects of different grassland vegetation restorations on species composition, diversity and biomass of poisonous plants in alpine meadow, the sample plots of natural grassland were imposed with sward ripping, reseeding, fertilization and integrated treatments. The results showed that there were significant differences in species compositions and proportions of poisonous plants in different sample plots (P0.05). Compared with the control, the species number and ShannonWiener index of poisonous plants in the communities were reduced significantly by treatments of reseeding, sward ripping and fertilization (P0.05). The order of species number and ShannonWiener index of poisonous plants in different sample plots was reseedingfertilization=integrated treatments sward rippingcontrol and reseedingsward rippingfertilizationcontrolintegrated treatments, respectively. At the same time, reseeding, fertilization and integrated treatments reduced the aboveground biomass of poisonous plants effectively (P0.05), but the sward ripping increased their aboveground biomass (P0.05). The order of aboveground biomass of poisonous plants was reseedingintegrated treatmentsfertilizationcontrolward ripping. In the reseeding plots, Elymus nutans became a single dominant community so that the species number, diversity index and aboveground biomass of poisonous plants were dropped to the lowest points. Thus, to improve the degraded grassland of noxious and miscellaneous grass type, reseeding is regarded as one of the optimal measures for grassland restoration.