Computerized morphometric characteristics of Gebel Watershed

Abstract

The study has been achieved on the Gebel watershed in the Kurdistan region (north of Iraq). The watershed drains on an area of 404.65 Km <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , this area is located between 43°49'45.899”E - 44°6'10.86”E longitude and 36°35'20.221 “N - 36°50'59.986”N latitude. The axial length and width of the watershed were 30.76 and 13.16 km respectively. Watershed elevations ranged from 322m to 1583m (m.s.l). The study included the estimation of morphometric parameters for the main watershed and other sub-watersheds, besides the network analysis. Remote sensing (RS) data and the implementation of the Geographic Information System (GIS) are combined for the watersheds morphometric characteristics study. Three groups of morphometric aspects (linear, areal, and relief) are categorized. The results showed that the values of aerial aspects (Form factor, Elongation Ratio, Circularity Ratio. Compactness Factor, Lemniscate Ratio, Drainage density, Constant of, Channel Maintenance, Stream Frequency, Infiltration Number, Drainage Texture), for Gebel watershed were (0.43, 0.74, 0.36, 2.80, 0.58, 0.89, 0.82, 0.89, 1.08, 3.02) respectively, Also, some variable such as streams order, streams length, bifurcation ratio were included in the Linear features. Gebel watershed stream orders ranged from 1 to 6, and for all orders, the total number of stream order recorded was (360), whereas the values of relief aspects (Watershed Relief, Relief Ratio, Relative Relief, Ruggedness Number, Hypsometric Integral) were (1.261, 40.99, 1.06, 1.53, 0.5) respectively. The current study will help manage the water resource and preserve the ecosystem of the Gebel watershed.