Almost all main terraces in Liwu Hsi, Hoping Hsi, and Fupuerh Hsi
are alluvial terraces or fill terraces. These terraces were
formed by the episodic river aggradation during rejuvenation in
late Holocene. The reason for episodic river aggradation of Liwu
drainage basin was not the deposition of landslide lakes and the
failure of nature dames, the landuse changes, the base level
rising, and the climatic changes. The complex response of
different fluvial systems, or different parts of a fluvial system
that ha or the beginnings of river downcutting and aggradation.