Utilization Of Alpine Grassland In Northern Tibet Euphorbia Resources

Alpine steppe of Northern Tibet is rich in resources of medicinal plants, it’s ecological environment extremely sensitive to disturbances, attribute to the special geographical location and climatic characteristics, the growth of medicinal plants in there as well as uniqueness. Our experiment develope on the alpine steppe of Nagqu, Northern Tibet. We investigate community characteristics of stellera chamaejasme L. both in gazing typical steppe and non-gazing typical steppe, ascertain by measuring differences in soil factors under different treatments. On the other hand, we apply HPLC measure the content of Umbelliferone and β-Sitosterol of Stellera chamaejasme L. during different phenophase in different plant organs, combine with local meteorological factor data, we analyze grazing disturbance impact on the productivity and quality of Stellera chamaejasme L. in northern Tibet, define the regular pattern of material and energy distribution, and the trends of content of the pharmacodynamic characteristic components in Stellera chamaejasme L. changes with the seasons, to explore the rational resource utilization mode of Stellera chamaejasme in northern Tibet.This research consists of three parts. The first part discusses grazing disturbance impacts the plant community on alpine steppe of Northern Tibet, especially the affect on resource populations of Stellera chamaejasme L., to show grazing disturbance impact on resource production of Stellera chamaejasme L. The second part of this study compares the differences of soil factors, community differences and meteorological factors which related with the growing of Stellera chamaejasme L. between different grazing treatments, to explain the reason of difference in production and quality of Stellera chamaejasme L. The last part of this research investigate difference in phenophase of Stellera chamaejasme L. and content of Umbelliferone and β-Sitosterol distributed at different growth stages between different grazing treatments. Provide the basis for reasonable harvest and make full use of the resources of Stellera chamaejasme L. The main conclusions are as follows:(1) After the implementation of prohibit grazing management on alpine grazing grassland in Northern Tibet, the grassland community coverage, height, above-ground and underground biomass, species diversity and richness increase significantly, in accordance with the classification of the functional group, the palatability of Graminoid and Cyperaceae species significantly increase productivity, the biomass of underground and aboveground of Stellera chamaejasme L. in grazing plots is higher.(2) Grazing plots and open grazing plots, increase soil porosity and water content, reduce soil bulk density, increase soil organic matter and nitrogen, and prevent the loss of soil metal nutrient elements, all of them differences greater in soil shallow.(3) After the implementation of grazing management, in the grasslands of Northern Tibet, the duration of breeding season last5days more, there are8days,15days and14days in advance during flower bud stage, flowering stage and fruit stage, breeding season of Stellera chamaejasme L. lasts longer, each phenophase advance and extend, but close to the time of phenophase ending,(4) The aerial parts of stellera chamaejasme L. also display contain effective medicinal characteristic components:umbelliferone andd β-sitosterol, even the highest of its content in the distribution of plants is in flower and fruit.(5) The most appropriate harvest time of stellera chamaejasme L. at Northern Tibet, is begin from late July to mid-August, and should gather the whole plant.