In order to analyze the spatial distribution and temporal change of rainfall erosivity in MinjiangRiver Basin

rainfall erosivity was calculated using daily data from 124stations during 1981-2010.Its spatial distribution map was created by Kriging interpolation.Based on Thiessen polygons theory and K-Meanscluster method

we divided the rainfall erosivity into three classes and analyzed the deviation coefficient

tendency coefficient and trend rate of each class.The results showed that annual rainfall erosivity was high insoutheast and lowered rapidly towards west.The rainfall erosivity was divided into three classes with clustercenter of 1 054.73

4 594.50and 7 153.75MJ·mm/(hm2·h·a)respectively.The area of low values wasmainly located in the upstream of the basin and its branch Dadu River basin

the area of intermediate valueswas mainly located in middle and lower reaches

and the high value area was found mainly in the regions ofYa'an

Leshan

Meishan and Dujiang weirs.The inter-annual variability differed spatially;more variationswere found in northern area than in southern area

as divided by the transect of Dujiangyan-Wenchuan-Xiaojin-Danba.Increasing inter-annual variability was found in the western part

whereas decreasing variability in the eastern part.The significance levels of changing trends differed spatially.