Analysis of Fluvial Morphometry and Prioritization of Pagla Jhora Micro Watershed of River Mahananda in Darjeeling District, West Bengal, India

Abstract

The morphometric analyses are of paramount significances in any type of hydrological study and it is compulsory in holistic management and qualitative improvisation of the target drainage basin. A critical examination and analyses of the morphometric yardsticks (Boulton in Morphometric analysis of river basin characteristics. Water Resource Board, 1968) and prominence of micro-watershed depending upon the water intake capacity of the Pagla Jhora sub-watershed has been taken into consideration in the current research work through the software-based evaluation of linear, relief and aerial aspects (Bull & McFadden in Geomorphology in Arid regions. State University of New York, pp. 115–138, 1977) of the study-area. Remote sensing and Geographic Information system have helped the researcher to focus on the study-area through Google-image and on further quantitative calculations (Chopra et al. in J Indian Soc Remote Sensing 33:531–539, 2005) of the manifold aspects of the drainage basin (Schumm in Geol Soc Am 67:597–646, 1956). In the basin area map, the overall arena of Pagla Jhora watershed in Mahananda basin (Clarke in Morphometry from maps, Essays in geomorphology. Elsevier, pp. 235–274, 1996) has been divided into total twenty eight sub-arenas and here the total basin has been divided under minor segments on the basis of the areal extents only. Thereafter the perimeter, area, absolute relief mean (Costa in J Hydrol 93:313–338, 1987), relative relief mean, elevation mean, hypsometric integral, bifurcation ratio, ruggedness number etc. have been traced out. Drainage density, form-ratio means (Das in Signatures of morpho-tectonic activities in western upland Maharashtra and Konkan region [Unpublished M.Sc. thesis]. Savitribai Phule Pune University, 2017) etc. have also turned up in the forefront through quantitative investigations. This research endeavour will not only focus upon the multiple morphometric analyses (Das & Pardeshi in Spat Inf Resour 26:47–57, 2018) depending upon the various aspects of the micro watershed of Mahananda River basin but also at the same time, the in-depth study will guide the target audience regarding the further explanation of such critical values of the morphometric techniques. From that perspective, the work may be geo-environmentally significant a lot.