S.C. Bhatt
Department of Geology, Bundelkhand University, Jhansi, Uttar Pradesh (India)
Sumit Mishra
HNB Garhwal University, Srinagar – Garhwal, Uttrakhand (India)
Rubal Singh
Department of Geology, Bundelkhand University, Jhansi, Uttar Pradesh (India)
Abstract
Rohni is a sub watershed of Dhasan river of Betwa river system. Geologicallyvarious types of granitoids of Bundelkhand Granitic complex, Meta-sedimentaryrocks of greenstone/superacrustal complex and TTG gneisses and othermetamorphics of Bundelkhand Gneissic complex are exposed within this basin.The Morphometric analysis of Rohni watershed was carried out by using remotesensing and GIS techniques and ASTR data. Based on hierarchical rank fivesub-watershed (5th order) streams are identified in the study area. The dendritic tosubdendritic drainage pattern is commonly observed.The drainage, density, slope and relief maps were prepared by using Arc GIS10 software and ASTER (DEM) data. The drainage orientation of Rohiniwatershed is represented by polymodal distribution (NE-SW, E-W and NW-SE).The corresponding trends of each watershed with Precambrian structures andhigh bifurcation ratio (7.00) suggest that the drainage pattern is structurallycontrolled. The variation in bifurcation ratio is due to strong influence of varioustypes of geological structures and lithology on drainage. The high value of RhoCoefficient is suggestive of high hydrologic storage during flood and shows lesseffect of erosion. The low value of form factor indicates that the basin is elongatedin shape and is less prone to flood. The circulatory ratio implies that the youthand mature stages are dominant in Rohini basin. The low drainage density (1.83)is indicative of presence of less permeable soil with low infiltration rate and lesserosion exposure in the basin. The low ruggedness and Melton ruggedness valuesindicates that the terrain is smother and less rugged and is a debris flood watershedless susceptible to soil erosion.
Key words: Rohni Watershed, Morphometric Analysis, Remote sensing and GISTechniques, Bundelkhand, Central India.
