Soil erosion pattern evolvement and their contributions to soil erosion and sediment delivery were qualified using a dual-box system with rainfall simulated experiment.The results showed rill head-cuts was dominant erosion form in initial stages of erosion evolvement process and hillslopoe sediment delivery gradually increased at hillslope in the middle stage of erosion evolvement process

gully head-cuts forward movement

channel deep-cutting

and gully-wall collapsing were dominant

which increased the sediment delivery dramatically;in the last stage of erosion evolvement process

gully development reached to a stable stage and sediment delivery fluctuated little.Gully erosion occupied 28.7%

70.4%

and 37.1% of the total sediment delivery in initial stages

in the middle stage

and in the last stage

respectively.