GIS-BASED WATERSHED MORPHOMETRIC ANALYSIS USING DEM DATA IN DIYALA RIVER, IRAQ
In this study, GIS and image processing techniques were employed to identify the morphological features and analyzing the basin properties of Diyala river. GIS hydrology tools were used for watershed delineation and analysis of the morphological features based on Shuttle Radar Topography Mission (SRTM) DEM data. Moreover, this study deals with the geometric characteristic, where it evaluates the sub-basins morphometric parameters such as area, perimeter, stream frequency, maximum width and length, drainage density and stream orders. The results led to delineate five sub-basins with five stream orders, the drainage density of these sub-basins are ringing between 0.47 to 0.99 km/km2. Stream orders were calculated, where the number of streams is 41494 with a length 7040.44 km as first order, 10747 with a length 3540.58 km as second-order, 59 with a total length 622.55 km as third order, 13 with a total length 454.98 km as fourth-order streams, and 5 with a total length 340.7 km as fifth order. The stream length reaches the maximum in the first-order, and it decreases with increasing the stream order. This result could be valuable for regional planners and overall policy-makers for agricultural/ water management strategies.