Assessment of wind-erosion risk in the watershed of the Ningxia-Inner Mongolia Reach of the Yellow River, northern China

Abstract

Abstract The watershed of the Ningxia-Inner Mongolia Reach of the Yellow River (NIMRYR) suffers from serious wind-erosion hazard from several deserts distributed in this watershed. A mass of aeolian sediment is fed into the Yellow River directly or by its tributaries, which clogs the channel and causes major disasters in local regions. To prevent siltation of the Yellow River, it is urgent to understand the spatial variability and patterns of wind erosion in the NIMRYR watershed. For this purpose, the Integrated Wind-Erosion Modelling System (IWEMS) and the Revised Wind-Erosion Equation (RWEQ) were used to estimate the potential wind erosion rate (PWER) and to map wind-erosion risk in this watershed. In this study, the IWEMS model was used to calculate the PWER in non-arable lands, and the PWER in arable lands was estimated by the RWEQ model. The results show that the average PWER in the NIMRYR watershed ranged between 0 and 31440.4 t/km 2 /a from 2001 to 2010. The areas with tolerable erosion, slight erosion, moderate erosion, severe erosion, very severe erosion, and destructive erosion occupied 31.04%, 38.13%, 22.89%, 6.46%, 0.93%, and 0.55% of the total watershed area, respectively. The assessment results showed that sandy lands have the highest wind-erosion risk and that the risk in arable lands is lowest. The average annual quantity of aeolian sediment blown into the NIMRYR was 15.87 Mt between 2001 and 2010, and that blown into the Ten Tributaries was 7.33 Mt.