Morphometric analysis and watershed delineation of the Karnaphuli river basin:A comparative study using different DEMs in Chittagong,Bangladesh  

作　　者：Sujit Kumar Roy Md.Arif Chowdhury 

机构地区：[1]Institute of Water and Flood Management,Bangladesh University of Engineering and Technology,Dhaka,Bangladesh [2]Department of Climate and Disaster Management,Jashore University of Science and Technology,Jashore,Bangladesh

出　　处：《River》2024年第4期426-437,共12页江河(英文)

摘　　要：The present study aimed to delineate a robust watershed boundary and extract its morphometric parameters in the Karnaphuli watershed,Bangladesh,using different digital elevation models(DEMs).Two DEMs,the shuttle radar topographic mission(SRTM)and the terra advanced spaceborne thermal emission and reflection radiometer(ASTER),were employed to delineate watershed boundaries and evaluate various morphometric characteristics.Raster data such as fill sinks,flow direction,and flow accumulation were utilized to delineate the watershed.The morphometric analysis included the estimation of linear,areal,and relief parameters.The findings revealed a noticeable difference between the datasets;ASTER delineated a larger watershed area than SRTM.Regarding stream order,there were streams ranging from 1st to 6th order,encompassing numerous small,medium,and main channels of the river.Drainage density was calculated as 0.52 km/km^(2)for SRTM and 0.51 km/km^(2)for ASTER,both having a spatial resolution of 30m.The bifurcation ratio ranged from 1.94 for SRTM to 2.45 for ASTER,indicating varying degrees of structural disturbance influenced by geological factors.The form factor indicated an elongated shape of the study area.The overall dimensions of the streams and the watershed extent suggest moderate mean annual rainfall discharge.The watershed exhibited relatively high denudation rates,attributed to the basin relief.A low drainage density indicated the importance of infiltration processes.The findings of this study provide valuable insights into the spatial variability of watershed characteristics,highlighting the need for tailored management strategies for the Karnaphuli River.Implementing targeted conservation measures and watershed management practices based on these morphometric parameters can enhance water resource sustainability and ecological health in the region.

关 键 词：ASTER DEM Drainage network Karnaphuli river Morphometric analysis SRTM Watershed 

分 类 号：S15[农业科学—土壤学]