Above-and below-ground biomass distribution of main alpine meadow plants and impact of degradation on root/shoot ratio and root area.

Understanding on distribution of above-and below-ground biomass and the effects of degradation on root/ shoot ratio and root area is crucial to predict the degraded processes in the alpine meadow. First, In Naqu Ecological and Environmental Observation and Research Station of Kobresia Fence (2009 enclosed) select native vegetationplace randomly selected Kobresia pygmaea, K. humilis, Stipa purpurea, Potentilla bifurca and Carex moorcroftii five species, degradation choice (compared with native vegetation) of Potentilla bifurca and Carex moorcroftii, then drying to constant weight and using a scanner to scan the surface area of roots. Finally, the use of different species and different levels of sampling two-way ANOVA to test the effects of above-and below-ground biomass, according to species and degraded state, the use of two-way ANOVA to test effects on aboveground biomass, and the use of the species, sampling levels and degraded state three-way ANOVA to examine the influence of biomass, root and shoot ratio and root surface area on Potentilla bifurca and Carex moorcroftii. Our results showed that belowground biomass of Kobresia pygmaea, K. humilis and Stipa purpurea mainly concentrated in the 0--10 cm soil layer which was about 70% of total belowground biomass of 0--30 cm, and belowground of 0--30 cm was about 96% of the total above-and below-ground biomass. Belowground biomass of 0--10 cm for Potenttilla bifurca and Carex moorcroftii was about 50% of the total belowground biomass of 0--30 cm. Belowground biomass of 0--30 cm for Potenttilla bifurca and Carex moorcroftii was about 57% and 85% of total above-and below-ground biomass respectively. As main plant species for the degraded alpine meadow, we found that degradation decreased aboveground biomass, belowground biomass, its root/shoot ratio and root surface area for Potenttilla bifurca; and it increased aboveground biomass but reduced root/shoot ratio for C. moorcroftii, whereas there was no significant effect on its belowground biomass and root surface area. [ABSTRACT FROM AUTHOR]