The North Channel is the north distributary of the second order bifurcation and one of the Changjiang Estuary's main channels into the sea.
北港水道是长江河口第二级分汊的北汊，长江的主要入海通道之一。
2
The riverbed form in different periods from 1958 to 2005 of the South Channel and the South-North-Passage bifurcation and the cross-section transformation between U-shape and W-shape are analyzed.