Due to the limited size of the experimental model the boundary effects were exaggerated; because of the small thickness of the bed layer channel closing could not take place, since the closing of one branch usually demands that the other branch is or may become capable, by erosion, of holding a larger flow; due to the lack of suspended load levees could not be formed; etc.

The morphological changes that took place at the channel fork under different test conditions were, however, rather similar to those observed in naturally branching channels. "Point-bars" were formed at the inside of the entrance to the branch channels, "pools" were excavated at and downstream of the point of bifurcation, the size of bed deformation was largest at the entrance to the branch channel that diverged at the greatest angle from the approach channel. When the equilibrium conditions were changed and the competency and capacity of one branch was decreased in relation to the other, aggradation took place at the entrance to the less efficient branch, while degradation took place in the more efficient. Lateral erosion at the downstream part of the channel fork was accompanied by accumulation at the upstream part of the channel fork.

One also has to consider that at natural channel forks the angle of divergence of a branch channel from the trunk stream may vary considerably with time, and that it often tends to increase when the efficiency of the branch channel decreases in relation to the other branch channel, due, for instance, to altered backwater conditions. At natural channel forks the less efficient branch therefore usually diverges at a greater angle from the trunk stream than the more efficient branch.

The morphological changes occurring at a channel fork reflect changes taking place upstream and downstream of the channel fork. The temporary angle of divergence of a branch channel from the trunk stream may therefore be regarded as a secondary factor.

 Of great importance for the diversion of sediment at channel forks and for their morphological development as well as that of channel bends in general is the direction of the bottom currents, since this is the very flow direction that influences the direction in which channel-forming deposits are carried.

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