Analyzing the hydrological characteristics and differentiation over the typical small basins in the upper reaches of the Weihe River

According to the measured hydrological and meteorological data over the two typical small basins in the Weihe River basin, the basin hydrological characteristics and differentiation with different climate and underlying surface were analyzed. It is found that in Qingyuan River and Niugu River basins the annual average air temperature is rising, the precipitation, runoff, silt discharge and precipitation runoff coefficient are totally decreasing; annual variations of precipitation, runoff and sediment are not the same. In 1998-2013, the precipitation of Qingyuan River basin decreased 8.6% as compared with that in the Niugu River. From 1993 to 2013, the runoff of Niugu River had decreased 21.4%; from 2000 to 2013, the silt discharge of Qingyuan River had decreased 24.0%. Between the two basins, the differences in area, river length, elevation and vegetation cover rate are-29.4%~-4.5%; the differences of air temperature and precipitation are-27.4%~16.7%; the difference in runoff is-90.2%~-84.7%; the difference i