Changes of land use have great impacts on terrestrial ecosystems.The trends of land use changes were analyzed based on the land,social,economic,and environmental data.Using the methods of the composite index and analytic hierarchy process(AHP),we established the ecological risk assessment systems considering natural,societal,and economic pressure,and evaluated ecological risk index and composite risks of land use structure including cultivated lands,forestlands,grazinglands,and water body.The results showed that the ecological risks were the greatest in cultivated lands,and smallest in water bodies.T he order of the risks is:cultivated land>woodland>land for inhabitation,mining and manufacturing > grazing and pasture land>unutilized land>land for transport facilities>land for water conservancy facilities.The ecological risks caused by economic pressure,nature pressure,and society pressure were greatest,intermediate,and smallest,respectively,while composite risk increased.The ecological risks are related to an unreasonable structure of land-use,increase in population,decrease in water resources and increase of natural disaster.