Author(s): Wenjing Shi; Zhaoyin Wang; Zhiwei Li
Keywords: YigongTsangpo River; Landslides; Vegetation restoration
Abstract: Landslides occur frequently on mountain rivers in the Qinghai-Tibet plateau, which destroy vegetation on the situ. Natural vegetation restoration might take a long period of time, depending on the climate and deposit material size distribution. Filed investigations and plot sampling were carried out on two large-scale landslides on the YigongTsangpo River, which happened in 1900 and 2000, respectively. Plant species were identified and diversity indices were calculated to study the vegetation restoration and succession on landslides. The results show that the vegetation coverage and total number of species increase with the age of landslides. The vegetation coverage reached approximately 30% on the 2000 landslide and almost 100% on the 1900 landslide in 2011. 26 species for 15 families were identified within the plot on the young landslide while 35 species for 25 families were found on the old landslide. Annual herbaceous species took a less proportion on the community of the 1900 landslide compared with that of the 2000 landslide. There was also significant increase in Shanon-weiner index and Pieloueveness index of the shrub layer and herbaceous layer. Even though several species were found on both 1900 and 2000 landslides, the dominant species of each layer were totally different. Populuswuana was the dominant and constructive species on the 2000 landslide but disappeared on the 1900 landslide, where it was replaced by Pinusdensata. The prosperity of understory layer species caused changes in moisture conditions, which finally made the environment unsuitable for Populuswuana and caused the vegetation succession on the landslides.