Extended data:
Yarlung Zangbo River Qushui area is called Yarlung Zangbo River in Tibetan, and the area where the river flows to Shannan is called Yalong River (named after a Yalong River song in Shannan). So this river is called Yalong River. However, in Qushui area, it is pronounced as Yarlung Zangbo River, because the accurate pronunciation of "Lu" in Tibetan is "Dragon", which means the river flowing through the valley plain above Qushui, so the whole river is called Yarlung Zangbo River.
References:
Baidu Encyclopedia-Yarlung Zangbo Grand Canyon
Baidu encyclopedia-Yarlung Zangbo River