The Main Shrubs Aboveground Biomass and Effect Factors in Yushu,Qinghai,China

In this paper,we study the main shrub types: Sibiraea laevigata( Linn.) Maxim. shrub; Rhododendron thymifolium Maxim. shrub; Spiraea myrtilloides Rehd. shrub; Potentilla fruticosa Linn. shrub; Salix oritrepha Schneid. shrub as the research objects,in the Yushu city,Qinghai province,China. We use the sample harvest method study and analysis the five shrubs aboveground biomass and its allocation patterns. Our results show that:the 5 types of shrub aboveground biomass fluctuated between 21. 61 ~ 34. 33 t /hm2,the largest aboveground biomass is Spiraea myrtilloides Rehd. shrub Potentilla fruticosa Linn. shrub,and the smallest is Potentilla fruticosa Linn. shrub,the average biomass is 29. 64 t /hm2. Different levels of the aboveground biomass order is: shrub layers herb layers litter layers,the proportions is 73. 35% 、14. 27% 、12. 35%,respectively. The dominant species aboveground biomass are arranged in order is that: Spiraea 1myrtilloides Rehd.,Potentilla fruticosa Linn. Rhododendron thymifolium Maxim Sibiraea laevigata( Linn.) Maxim. Salix oritrepha Schneid. The shrub aboveground biomass of decline with the rise the altitude,and increase with the community coverage and shrub height.Grazing on shrub aboveground biomass mechanism is not clear.