Braided rivers: structure, types and hydrological effects

摘要

Braided rivers have been intensively analyzed mostly by geomorphologists. In the present study the approach to recognize braided channel types and effects with the special emphasis on flow partitioning has been applied. It is assumed that each braided channel represents the reach which is initiated with dividing of the single channel and completed below the confluence of the total multiplicity of channels. Proposed indices of braided channel structure and water discharges ratio which have been proposed and applied to 200 braided reaches of 40 rivers in Russia, China, and the USA enable the description of the origin and types of the observed rivers and further analysis of hydrological effects of braided channels. The latter represent physical, hydrochemical, and ecological conditions of stream along braided reaches caused by flow distribution among branches in relation to braiding intensity. Structure and braided channel pattern types impact on hydraulics, sediment transport, water temperatures, and stream communities are of primary interest in the present study.