Runoff spatial difference of small-scale in Huangnan, Qinghai province and its cause

Meso-and large-scale hydrological measurements cannot indicate the spatial difference of small watershed. For exploring the spatial difference of small-scale runoff, the fifty rivers in Huangnan, Qinghai with the sampled area in 10-100 km² are measured on August 14 to 23, 2013. Moreover, the temporal upscaling are also conducted. The results show that the differences of daily discharge modulus could be 20 times higher. It could be more than 4 times even for the regions with similar precipitation. We find the runoff synchronicity in normal season for 3 stations with meso-scale measurements. Based on this character, the daily runoff properity can be deduced to annual time scale. The precipitation and slope could play a dominant role in the spatial difference of small-scale runoff. The reconstructed precipitation, precipitation loss and slope runoff model in this study can provide a useful tool in spatial scale conversion and accuracy improvement of hydrological analysis.