Reservoir sedimentation and transformation of morphology in the lower yellow river during 10 year's initial operation of the Xiaolangdi reservoir

The Xiaolangdi Hydro-Project is one of the large projects on the main stem of the Middle Yellow River. It has been operated for more than 10 years, since its impoundment in October, 1999. The reservoir has trapped 2.833×109 m3 of sediment, and caused the total erosion of 1.891×109 t in the Lower Yellow River from October, 1999 through October, 2010. Not only the serious atrophied situation of the Lower Yellow River (LYR) has been resuscitating, but also many new phenomena of sediment transport and behaviors of channel re-establishing are coming into being. They are illustrated and discussed in detail in this paper.