Remote sensing and gis application for morphometric analysis of upper mat watershed, Serchhip District, Mizoram Barman Binoy Kumar, Gogoi Chandrika, Rao K. Srinivasa* Department of Geology, Mizoram University, Aizawl, India *Email: srkoduri4@yahoo.co.uk
Online published on 22 May, 2019. Abstract Morphometry is of immense utility in watershed prioritization and conservation of natural resources at watershed level. The six sub-catchments namely A to F of Mat Watershed were analysed in the present study and morphometric analysis was carried out by using the Arc GIS software and SRTM Digital Elevation Model (DEM). The geographic location of the study area lies between latitudes 230202 03 N to 230312 503 N and longitudes 920442 503 E to 920512 403 E and falls in parts of Survey of India Toposheet numbers 84A/11, 84A/14 and 84A/15 covering an area of 130.51km2. The drainage pattern observed in the study area is trellis, dendritic and parallel in pattern. The drainage density of Upper Mat Watershed is 3.89 km−1 and the Sub-basins B, C, D, E are of high drainage density. The high drainage density is the result of weak or impermeable subsurface material, sparse vegetation and mountaneous (high) relief. The stream frequency in the study area is 5.76 streams/km2, whereas the fourth order stream frequency varies from 5 to 7.65 streams/km2. The high stream frequency values suggest that the relatively resistant subsurface strata is covered with sparse vegetation coupled with high relief and low permeability rock formations in the study area. The circularity ratio of the entire basin is 0.42 and the sub-watershed values range from 0.43 to 0.68 indicating that the basin has lower circulatory ratios suggesting high relief and an impermeable surface resulting in lower basin lag times. The drainage texture values range from 21.11 to 120.41 per km. indicating that all the sub-watersheds fall under the very fine texture category. Dissection index calculated for the Upper Mat Watershed area is 0.02 and the sub-watershed values vary from 0.06 to 0.26, suggesting that the study area is a vertical cliff in nature and in a mature stage of landform development. The relief ratio of the watershed is 0.027 and the sub-watershed values range from 0.051 to 0.118. Low values of relief ratio indicate that the study area has less resistant rocks like shales, siltstones and sandstones. Top Keywords Morphometry, Remote Sensing, SRTM, Mat Watershed, Serchhip, Mizoram. Top |