The areas of forestry in the upper reach and lakes in the lower reach of many watersheds have been on the decrease, so the flood problem has become mo re frequent and worse in China. Great attention must be paid to research about t he effect of the changing landscape structure on the hydrological process of wat ershed.; The watershed in study here, Sihu watershed in Hubei, China, is a plain consisti ng of paddy field, fishpond, lake and dry land. There were different runoff-yie l d models for the four kin...