Response of grass productivity potential to climate changing in south of Guanshan

PU Jin-yong~(1,2),YAO Xiao-ying~3,YIN Dong~4,WANG Liping~5,YAO Xiao-hong~2(1.Lanzhou Institute of Arid Meteorology,China Meteorological Administration,Key Laboratory of Arid climate Change and Reducing Disaster of Gansu Province, Lanzhou,Gansu 730020,China;2.The Agrometeorological Experimental Station of Tianshui,Tianshui,Gansu 741020,China: 3.TianShui Meteorological Bureau,Tianshui,Gansu 741000,China;4.Gansu Province Meteorological Bureau,Lanzhou,Gansu 730020,China;5.Qingshui Meteorological Bureau,Qingshui,Gansu,741500,China)

south of Guanshan;grass productivity potential;climate changing;responding

Based on meteorological data of Qingshui and Zhangchuan weather station and the cattle population of these two counties,the law of climatic variation had been analyzed with mathematical statistic method,the grass climate productive potential had been calculated and the variation of cattle population had been reviewed.The results show that the annual mean temperature rose by 0.7～0.8℃ during last 35 years,the precipitation reduced by 50 mm in last 30 years.The main meteorological limit factor of forage grass production was precipitation,the thermal productive potential increased by 3 080 kg/hm~2,and the precipitation productive potential reduced by 841 kg/hm~2.The thermal and water did not match well during the period of grass growth,and the really productivity is coming down. The primary livestock productivity almost approached its limit in south of Guanshan.The next step of livestock develop of Guanshan should lie in fine processing and making full use of livestock product.