Integrated monitoring of alpine vegetation types and its primary production

In this paper, species composition, biomass change pattern and differences of 2 types of alpine vegetations in the northeastern part of Qinghai were analyzed. Monitoring results showed that there were significant differences in soil humidity moisture and evaporation between Kobresia humilis meadow and Potentilla fruticosa shrub which grew in the same regions with similar altitudes and precipitation but different topography. The species constitute 2 types of alpine vegetations which are different due to limitations of environmental factors, especially soil temperature and moisture. With respect to the general biogeography of the region, the Potentilla fruticosa shrubs, dominated by Potentilla fruticosa and accompanied with Kobresia capillifolia, Kobresia pygmaes, Festuca ovina and some forbs, are found on the northern slopes. The Kobresia humilis meadows, typical alpine meadow dominated by Kobresia humilis and accompanied with Elymus mutans, are widely distributed along the valley floor. The above-ground biomass of Kobresia humilis meadow is greater than that of Potentilla fruticosa shrub. As for underground biomass (0-40 cm), both types of vegetations maintained relatively great values during the period from May to September, but the occurrence time of its peak value and the lowest value differs from each other for the 2 types of vegetations. The annual net underground production of Potentilla fruticosa shrub is greater than that of Kobresia humilis meadow, whereas, the turnover value of underground production of Kobresia humilis meadow is greater than that of Potentilla fruticosa shrub.