论文摘要
Based on fieldwork and the longitudinal section obtained by ArcGIS, seven major knickpoints in Songlin River Basin are located. It is found that the regions with a great average elevation difference between ridge and valley suffer more from disasters such as collapse, landslides, and debris flows. Dimensionless number Vindex is used to quantitatively describe the cross-section of the Songlin River Valley. The Vindex coefficient is below 0 outside the upstream influence of knickpoint and in downstream of knickpoint and it is over 0 in the upstream of knickpoint and at the knickpoint. The overall change trend is "super V shape-U shape-super V shape". The formation and development of knickpoints strongly influence the geomorphological characteristics of the Songlin River Basin. Due to the rising erosion base level of the upstream of knickpoint, sediment is deposited and the incision rate of riverbed decreases or it even stops down cutting. In this way, the average elevation difference between ridge and valley is tend to reduce, which lowers the energy that causes geological hazards and improves the stability of the upstream. The gradient of both riverbanks decreases, forming a flat and wide U-shaped river valley. Although the elevation difference between the river and the downstream watershed of the knickpoint remains constant, the current energy increases and the erosion is still severe, keeping the valley in a V shape.
论文目录
文章来源
类型: 国际会议
作者: Tan Long,Tang Di,Wu Xuefeng,Qi Lijiang
来源: IAECST-International Conference on Architecture,Civil and Hydraulic Engineering（ACHE 2019） 2019-12-20
年度: 2019
分类: 基础科学,工程科技Ⅱ辑
专业: 地球物理学,水利水电工程
单位: College of Water Resources and Hydropower,Sichuan Agricultural University
分类号: TV147
DOI: 10.26914/c.cnkihy.2019.069510
页码: 182-189
总页数: 8
文件大小: 850k