Author(s): Cheng Liu, An Liu
Keywords: Yellow River source region; River bend; Migration rate; Tree ring analysis; Remote sensing image;
Abstract: A meandering river has dynamic geomorphological evolution characteristics of creeping movement, and studies on evolution process of the meandering river have both scientific significance and engineering practice value. The source region of the Yellow River is located in the northeastern part of the Qinghai-Tibet Plateau, where meandering rivers are extensively developed. Due to the source region is inaccessible and lacking of long-term river monitoring data, studies on river evolution process in this region are difficult. Combined with the field investigation and sampling in the source region of the Yellow River in 2016 and 2017, total 9 river bends of the Baihe River, a typical meandering river, are selected as an example to analyze the evolution process of the river with help of tree ring analyses in this paper. The vegetation distribution in the convex bank of the river bends was analyzed, and the tree ages were obtained by tree ring analysis. The method of estimating the migration rate of a river bend using the tree rings analysis was proposed base on the relationship between convex bank growth with sediment deposition and the vegetation succession. The estimated migration rates of the river bends of the Baihe River range (0.38-6.10) m/yr, which are basically consistent to the scales of the rates estimated by using remote sensing images. The comparison results indicated that the migration rates of the river bends estimated by the tree ring analysis were acceptable.