A total of 80sampling sites were selected in the Liaohe River basin.During the period of 2009-2010

physical-chemical variables were analyzed to facilitate comprehensive water quality assessment and inparticular to address its relationship with land use/cover.The results indicated that physical and chemicalproperties showed apparent spatial heterogeneity in the basin.As located in the southeast

little pollutionwas imposed on Taizihe River and Hunhe River

where water quality in downstream reaching level ofⅤorslightly lower thanⅤ.Xilamulunhe River and Laohahe River

located in the northwest of the basin

hadwater quality ranging betweenⅣandⅤ.There were no obvious features in the East Liaohe River basin

where water quality in downstream was classified as worse thanⅤlevel in 2009and was ranging betweenⅢandⅤin 2010.The majority of West Liaohe River was dry for many years.Big Liaohe River basin was located in middle and eastern

with water quality varied aroundⅤ.Correlation and regression analysis indicatedthat forest and agriculture were the major land use types in the watershed scale affecting water quality variables including CODMn

sediment

conductivity and TN.Grassland showed positive effect significantly on thecomprehensive water quality in 2009.