ABSTRACT

The current study explores the planform morphological changes that have occurred in the upper segment of the Yamuna River by using Landsat images from 1979 to 2019. The river segment was divided into 18 sections at equal spacing, viz., S1 to S18, and the centerline and bank line shifting, channel width, alterations in meander geometry and braiding characteristics in terms of sinuosity index (SI) and braiding index (BI) were evaluated. The results indicate a maximum centerline shifting eastward at section S-5 and westward at S17 during 1999, with respect to the base year of 1979. The average eastward and westward centerline shifting remained insignificant. The average west bank shifting ranged from 0.407 km to 0.892 km east and 0.440 km to 0.418 km west, indicating relatively higher west bank shifting towards east. The average east bank shifting ranged from 0.335 km to 0.505 km east and 0.344 km to 0.896 km west, indicating a narrowing of the bank width throughout the segment length. During the assessment period, the river segment exhibited sinuous characteristics and non-braided behavior. The outcomes of this study could be useful in predicting future trends in river shifting and developing sustainable land use planning strategies along floodplains.

摘要

本研究利用1979年至2019年的Landsat影像探讨了亚穆纳河上游发生的平面形态变化。河段被等间距分为18个断​​面，即S1至S18，中心线河岸线移动、河道宽度、曲流几何形状的变化以及蜿蜒指数 ( SI ) 和编织指数 ( BI)方面的编织特征）进行了评估。结果表明，相对于 1979 年基准年，1999 年期间，最大中心线东移位于 S-5 剖面，西移位于 S17。平均中心线东移和西移仍然不显着。西岸平均向东移动0.407公里至0.892公里，向西移动0.440公里至0.418公里，表明西岸向东移动相对较高。东岸平均移动范围为向东 0.335 公里至 0.505 公里，向西 0.344 公里至 0.896 公里，表明整个路段长度上岸宽变窄。在评估期间，河段表现出蜿蜒的特征和非辫状行为。这项研究的结果可有助于预测河流转移的未来趋势和制定洪泛区可持续土地利用规划策略。