GIS based drainage morphometry and its influence on hydrology inparts ofWestern Ghats region, Maharashtra, India

Abstract

A c c e p t e d M a n u s c r i p t RESEARCH ARTICLEGIS based drainage morphometry and its influence on hydrology in parts of Western Ghats region, Maharashtra, IndiaVarious drainage morphometric parameters in the Upper Bhima river basin and its influence on hydrological processes (e.g runoff, peak flow, time to peak, infiltration, overland flow etc.) were discussed using Geographical Information System (GIS) and Remote Sensing (RS) techniques. Survey of India (SoI) topographical maps and ASTER Digital Elevation Model (DEM) was incorporated for thematic database generation and morphometric parameter evaluation. Total study basin was divided into 8 sub-basins so that the spatial variation of morphological parameters and its influence on hydrology could be analysed. The interrelationship between morphometric variables were computed (p <0.05) and presented in a correlation matrix. The study revealed that, mean basin slope (B s ), drainage density (D), length of overland flow (L g ) and basin relief (H) are significantly related with a large number of morphometric variables. Due to close proximity of Western Ghats, sub-basins 1, 2, 4, 5 and 6 are highly influenced by slope as result, length of overland flow decreases and water immediately follow channel path. In contrast, sub-basins 3, 7 and 8 are relatively flatter, overland flow is relatively longer and favourable for infiltration. Independent morphometric variables were identified from correlation matrix and used in a Multiple Criteria Analysis (MCA) framework for watershed prioritization. Analytical Hierarchical Process (AHP), a MCA technique, identified the highest (sub-basin 4) and lowest (sub-basin 7) priority sub-basins in the Upper Bhima basin. The outcome of the study may be useful for watershed managers and planners while implementing soil and water conservation measures in the region.

Monitoring land use changes associated with urbanization: An object based image analysis approach

“…The western margin the basin is highly rugged due to presence of Western Ghats which gradually merges towards basin outlet. Due to natural barrier, the western part of the basin receives more than 3000 mm of rainfall and decreases towards east [Samal and Gedam, 2015]. Heavy rainfall in Ghats region leads to construction of several reservoirs for storing water and use it during non-monsoon months.…”

Identification of erosion-prone areas using modified morphometric prioritization method and sediment production rate: a remote sensing and GIS approach

“…The peripheral areas of sub-watersheds in present study show steep slopes where first and second order streams are concentrated ( Figure 5). High average slopes in sub-watershed 1 is ranked 14 with increased stream flow velocity, minimized length of overland flow and quick water flow into streams contributing to hydrograph rise (Samal et al 2015). It has been observed that subwatershed 12 has low average slopes and therefore ranked 1 (Table 2) shows less runoff, relatively less land erosion and low peaks in hydrograph.…”

Hydrological inferences through morphometric analysis of lower Kosi river basin of India for water resource management based on remote sensing data

“…Basin relief is a key indicator of a drainage system shown by the elevation (Samal et al 2015). The 'Rhl' is the ratio between the total relief and the lengthiest measurement of the basin parallel to the main drainage line (Schumm 1956) and it is directly related to the 'Lg' and time to peak.…”

“…High 'C' value in any basin displays the basin area of lower stream order drainages are fairly larger than the sub-basins which have lower C value. Low 'C' value in the basin reduces length of overland flow (Lg), thus water discharges rapidly as channel flow in scant vegetation cover (Samal et al 2015).…”

“…The interrelationship between morphometric parameters differs from one river basin to another basin under varied topographical and climatic condition. Understanding these relationships would enable us to recognize the dominant variables acting on a particular river basin (Samal et al 2015). Hence the fluvial geomorphology is essentially connected with the river basin geometry and its channel network.…”