Shifting Analysis of a River in Tarai Region Using Spatio-Temporal Satellite Imageries
摘要
Rivers flowing through the flatland of Tarai region experiences frequent changes of water levels and exhibits shifting of the river courses. Changes in the hydrological and geomorphology conditions as well as human interventions induce morphological changes in the river causing several environmental and socio-economic issues. The Kichcha River originates from Kumaun hills exhibits severe sifting when it enters in the floodplain in the Tarai region. In this study geospatial techniques have been used to understand the morphological behaviours and quantify the spatio-temporal shifting of the Kichcha River channel over a period of 30 years (1993–2023). Terrain analysis of the study area was carried out using ALOS PALSAR DEM. To understand the morphometric and shifting analysis, the entire reach of the study region is divided into 8 sections (reaches) based on the variation of the stream slope. The morphological behaviours were measured in terms of sinuosity index, and entrenchment (E) ratio. The analysis showed that Section 4 is the most suitable reach. Further, the Year-wise trend of bank shifting with respect to river course line of the year 1993 of Kichcha River also showed the minimal shifting in Section 4 and significant shifting in Section 7. This study highlights the use of temporal satellite images for the morphological and spatio-temporal river shifting analysis. The river course shifting analysis helps in identifications of problematic river reaches and accordingly plan for the anti-erosion and anti-flow fighting measures.