Drainage morphometric analysis for assessing form and processes of the watersheds of Pachamalai hills and its adjoinings, Central Tamil Nadu, India

Abstract

The present study attempts to understand the form and geomorphic/hydrologic processes of the 20 watersheds of the Pachamalai hills and its adjoinings located in Tamil Nadu State of southern India from the analysis of its drainage morphometric characteristics. Survey of India's topographic sheets of 1:50,000 is the data source from which stream networks and watersheds of the study area were demarcated followed by the analysis of their morphometric characteristics using ArcGIS software. The results of the analysis formed the basis for deducing the form and processes of the watersheds of the study area. The form of the watersheds inferred from the analysis includes shape, length, slope steepness and length, degree of branching of streams, dissection and elongation of watersheds. The geomorphic/hydrologic processes inferred include denudation rate, potential energy, intensity of erosion, mean annual run off, mean discharge, discharge rate, rock resistivity and infiltration potential, amount of sediment transported, mean annual rainfall, rainfall intensity, lagtime, flash flood potential, flood discharge per unit area, sediment yield and speed of the water flow in the streams. The understanding of variations of form and processes mentioned can be used towards prioritizing the watersheds for development, management and conservation planning.

Morphometric analysis and prioritization of upper Benue River watershed, Northern Nigeria

“…This means that the number of streams usually decreases in geometric progression as the stream order increases (Horton 1945). This confirms the findings of Pophare and Balpande (2014) that the difference in rock structure is responsible for the different stream order. The 1st and 2nd stream orders, respectively, constitute 57.89% and 26.87% of the watershed originating from the mountains and hills with a steep/moderate slope and are usually seasonal.…”

The Implementation of a Hybrid Model for Hilly Sub-Watershed Prioritization Using Morphometric Variables: Case Study in India

“…To prioritize nine SW of BW, 3 significant morphometric variables (F s , L om and F f ) were considered. The cross-correlation between the 3 variables was performed as shown in Table 11 while CF was used as a factor to determine the priority rank (PR) of the 9 SW using Equation (19) as presented in Table 12. The calculation of the weight values assigned to each morphometric parameter was done by using the grand total of correlations to divide each variables' sum of correlation coefficient (Table 11).…”

“…The authors suggested different thematic maps integrated with morphometric variables to determine the suitable areas for citing water and soil conservation measures. In India, several studies on watershed prioritization have been performed based on morphometric analysis using the potential of RS and GIS techniques [15][16][17][18][19][20][21][22].…”

Variation in species assemblages due to micro-topography and flow regime govern vegetation carbon stock in seasonal floodplain wetlands

“…We attribute these to the variations in the wetland microtopographic characteristics such as depth, width, and crosssectional area in the sampling stations across the wetland. Several other studies have also inferred that the topographic characteristics of aquatic ecosystems are among the significant determinants of flow variation (Wetzel 2001;Camila de Sousa et al 2011;Yunus et al 2003;Singh et al 2014;Pandi et al 2017;Soni 2017;Prabhakaran and Raj 2018), which in turn create heterogeneous micro-environments within wetlands.…”