Effects of land use change on runoff in the typical areas in Haihe River basin

In order to research the reaction of the runoff of Haihe River basin towards the change of land use, Fuping basin, Kuangmenkou basin and Jiehepu basin were regarded as the research areas and the data of hydro meteorology from 1970 to 2011 were combined to analyze the space-time transfer characteristics of different land use. Moreover, four scenarios of land use were set in combination of SWAT (Soil and Water Assessment Tool) model and influence on runoff by the change of land use types was evaluated. Result showed that this model could better simulate monthly flow process of the whole year as well as in flood seasons. The runoff had experienced a gradual decrease for many years and it fluctuated from 1980s to the middle of 1990s. The transformation in time and space among different types of land use presented the reversibility and major changes included an increase in forest, a decrease in grassland and a little increase in agricultural land. The increase of forest and the decrease of grassland would cause a decrease of runoff in flood season and the maximum monthly peak discharge. The coefficient in flood season decreased with the increase of forest area. Therefore, it was very important to properly plan land use pattern so as to control watershed hydrological events.