Morphologic parameters of a watershed could help in segregating critical sub-watersheds for taking up conservation practices and mitigation interventions. Determination of critical watersheds or prioritization of sub-watersheds is inevitable for efficient and sustainable watershed management programs and allocation of its natural resources. The traditional methods of determination of morphologic parameters are time consuming, expensive and requires huge labor. However, the process becomes easier, cheaper and faster with the advent of Geographical Information System (GIS) and remote sensing technologies. In the present study, a combined approach of using toposheet, remotely sensed digital elevation model and morphometric ArcGIS toolbox has been adopted to determine morphometric parameters in Dudhnai river basin, a sub-basin of river Brahmaputra which is prone to both erosion and sedimentation. Seven sub-watersheds of Dudhnai have been prioritized by using the morphometric parameters and ranked them according to its vulnerability to soil erosion. The results of bifurcation ratio, drainage density, drainage intensity and constant of channel maintenance showed that Dudhnai watershed is a well-dissected watershed with less risk to flooding and soil erosion. However, significantly high values of infiltration number and ruggedness number obtained are indicative of very low infiltration which may result in high surface runoff and soil erosion. The study also revealed that channel erosion is stronger than sheet erosion in the basin. The prioritization of the sub-watersheds implied that Chil sub-watershed is the most susceptible sub-watershed that needs greater attention for soil and water conservation measures. The results of the present study could aid various stakeholders who are involved in the watershed development and management programs.

流域的形态参数有助于隔离关键的子流域，以采取保护措施和缓解干预措施。确定关键流域或对子流域进行优先排序对于高效和可持续的流域管理计划及其自然资源的分配来说是不可避免的。传统的形态学参数测定方法耗时、昂贵且需要大量劳动力。然而，随着地理信息系统 (GIS) 和遥感技术的出现，这个过程变得更容易、更便宜和更快。在本研究中，采用地形图、遥感数字高程模型和地形测量 ArcGIS 工具箱相结合的方法来确定 Dudhnai 河流域的地形测量参数，雅鲁藏布江的一个子流域，易于侵蚀和沉积。Dudhnai 的七个子流域已通过使用形态测量参数进行了优先排序，并根据其对土壤侵蚀的脆弱性对其进行了排名。分岔比、排水密度、排水强度和渠道维护常数的结果表明，Dudhnai 流域是一个解剖良好的流域，洪水和水土流失的风险较小。然而，获得的入渗数和崎岖度数的显着高值表明非常低的入渗，这可能导致高地表径流和土壤侵蚀。研究还表明，盆地中的河道侵蚀强于片状侵蚀。子流域的优先级意味着 Chil 子流域是最易受影响的子流域，需要更多地关注水土保持措施。本研究的结果可以帮助参与流域开发和管理计划的各种利益相关者。