Hydrological processes in different landscapes on Mafengou River basin

There is less research about integrated hydrological processes in alpine cold regions at present. This paper aims to explore the hydrological processes in different landscapes on the Mafengou River basin of an alpine cold region. This is done through the identification of the composition of alpine runoff of different origins including glacier, snow, frozen soil, surface water, groundwater, and precipitation using isotope and hydrochemical methods. A mixing model is employed for hydrograph separation. The result shows that the groundwater from the alpine cold desert zone and shrub zone contributes about 52% of river discharge in the Mafengou River during the wet seasons. The recharge of groundwater is achieved by transforming thawed frozen soil water into river channels, and infiltrating glacier snow melt water and precipitation on the land surface. Other contributions include 11% melt water directly coming from the glacier snow zone, 20% surface runoff on the alpine cold desert zone and alpine shrub meadow zone, 9% thawed frozen soil water from the alpine grassland zone, and 8% precipitation water. The study suggests that the direct runoff generated from precipitation events rarely occurs over the whole basin. Much precipitation will infiltrate into the soil either becoming interflow or recharging groundwater, and then drain into river channels.