The spatiotemporal trend of vegetation coverage in Beiluo River watershed was analyzed to understand the eco-environmental evolution and runoff-sediment behaviors on the Loess Plateau.TM images of 1987

1995and 2007with a spatial resolution of 30mwere employed

the normalized difference vegetation index(NDVI)was then calculated

and the dimidiate pixel model was used to get vegetation coverage degrees and its classification.Results showed that(1)under the double influences of climate change and human activities

the vegetation coverage in Beiluo River watershed experienced the process of slow to rapid increase from 1987to 2007.The vegetation coverage degrees for the whole watershed were 41.12%

46.43% and 63.43%in 1987

1995and 2007

respectively.(2)The vegetation coverage both in the hilly-gully and tablegully regions showed a slow to rapid trend from 1987to 2007

and the rocky-mountain region kept the relatively stable forest coverage.The intense vegetation restoration mainly occurred in Wuqi and Zhidan Counties and Luochuan tableland in the watershed.