Figure 4 Changes in snowpack at different elevation slopes of the Mamukao River during spring and winter. (a, b. Spring and winter altitude; c, d Spring and winter slope direction)
The ablation rates of different slope directions in the Mamukao River Basin exhibited variation (Fig 4(c, d)). During spring, the ablation rates followed the following order: south slope > west slope > east slope > north slope, with the south slope experiencing the highest rate of ablation and the north slope the lowest. Conversely, in winter, the ablation rates followed this order: west slope > east slope > south slope > north slope, with the west slope exhibiting the highest rate of ablation and the north slope the lowest. The north slope consistently demonstrated the lowest ablation rate in both winter and spring, likely due to the relatively flat topography of the Mamukao River and its location on the shaded side during these seasons, resulting in reduced solar radiation and consequently lower rates of ablation compared to the other three slopes. In winter, the south slope displayed the fastest ablation rate, attributable to the low precipitation during this season and the increased solar radiation received. In spring, the east and south slopes, being windward slopes, experienced precipitation that slowed down the ablation rate, whereas the west slope, located on the leeward side with lower precipitation, exhibited the highest ablation rate. Additionally, the northward movement of the sun during spring resulted in reduced radiation received by the south slope, further contributing to the west slope’s relatively greater ablation rate.