Dynamic changes of grazing pressure on grassland on south slope of Guanshan Mountains over the last 30 years

YAO Xiao-ying1,2,PU Jin-yong3,YAO Ru-xin4,ZHANG Meng-lan5(1.Lanzhou Institute of Arid Meteorology,China Meteorological Administration,Key Laboratory of Arid Climate Change and Reducing Disaster of Gansu Province,Open Laboratory of ClimateChange and Disaster Reduction of China Meteorological Administration,Gansu Lanzhou 730020,China;2.Tianshui Meteorological Bureau,Gansu Tianshui 741000,China;3.Agro-meteorological Experimental Station of Tianshui,Gansu Tianshui 741020,China;4.Shimaping Middle School,Gansu Tianshui 741020,China;5.Tianshui Statistics Bureau,Gansu Tianshui 741000,China)

south of Guanshan;grassland;press;variation;Tianshui City

The safe and health of grassland ecosystem is very important for the sustainable development of animal husbandry.Based on the animal population data in the area of south slope of Guanshan and the climate data regarding to sunshine duration,temperature and precipitation in Qingshui and Zhangjiachuan Weather Stations in 1978 to 2008,the model of grassland pressure index was established to analyze the dynamic variation of animal population,grassland potential production and pressure index.The result showed that the annual animal population increase was 1.76×104 sheep units;potential grassland production changed little and ecological pressure index increase was 0.2 since 1978.It indicated that the ecological pressure index increased greatly in the last 5 years and the animal population was over the capacity of the grassland.The main way for sustainable animal husbandry development was to control the animal population and expand the grassland area.