Change of grassland productivity and countermeasure in Aletai Prefecture,Xinjiang Province

Based on the integration of remote sensing and geographic information system and field survey,the study collected the historical dates(grassland classification map,grassland gradation map,grazing map before 1985)to combine MODIS data in 2009 and the yield data in field for research analysis and management strategies.The ratios of available grassland(K1),edible forage(K2),and grassland use(K3),were determined,forage yield model for each type of seasonal grassland was established,forage yield,theoretic stocking rate,seasonal grassland stocking rate and grassland gradation for whole prefecture and each county were calculated,the comparison analysis of theoretic,threshold and practical stocking rate were provided,as well as information of grassland productivity change and relevant countermeasure for whole prefecture and each county.