Comment on "Constraining tectonic uplift and advection from the main drainage divide of a mountain belt" by C. He et al.

He et al. (2021) combined numerical landscape evolution modeling and analytical solutions to demonstrate that mountain asymmetry, determined by the location of the main drainage divide, increases with increasing uplift gradient and advection velocity gradient, which promotes a better understanding of the tectonic influence for the main drainage divide. However, their analytical solution on the relationship between uplift gradient and normalized divide location (Fig. 2e in He et al., 2021) is only applicable when the conditions (the lower uplift rate of 0.5 mm/yr and mountain width of 50 km) are met. According to our numerical modeling, there is no stable relationship between uplift gradient and normalized divide location, when one of the above conditions is changed. Instead, there might be a correlation between the ratio of uplift rate on two edges and normalized divide location