Morphometric Assessment of Wadi Wala Watershed, Southern Jordan Using ASTER (DEM) and GIS

Abstract

Morphometric analysis is of vital concern to understand hydromophological processes in a given watershed, and thus, it is a priority for assessing water resources in drainage basins. A morphometric analysis was conducted to identify the drainage properties of Wadi Wala and the 23 fourth-order subbasins. ASTER DEM data was employed to compile slope, elevation, and aspect maps. Arc GIS software was used to measure and calculate basic, derived and shape morphometric parameters. W. Wala is found to be a sixth-order drainage basin, and the drainage pattern is trellis to sub-trellis in the central and lower part of the catchment, whereas it is dendritic to sub-dendritic pattern in the southern and northern parts. The slopes of the catchment vary from 0˚ -5˚ to >35˚ in slope categories. Tectonic uplifting and tilting, lithology, structure and rejuvenation are the major factors controlling morphological variation over the watershed. The recognized fault systems are chiefly controlling the drainage pattern, and the elongated shape of the sub-basins is attributed to dense lineaments in the central and eastern parts of the watershed. The R b values for the entire catchment and the sub-catchments range from 2 to 7, with a mean of 4.55, which indicates the distortion of drainage pattern by geological structure. Hypsometric integral values are high for the W. Wala watershed and the sub-basins, where it ranges from 70% to 89%. High HI values indicate that drainage basins are at the youth-age stage of geomorphic development, and they are affected by tectonic uplifting, tilting, and the dominance of hillslope process. Variation in HI values is apparent between sub-basins located at the western part, or, the rejuvenated belt where HI values range from 85% to 89%. Whereas the HI values of the sub-basins located at the eastern part of the watershed, vary from 70% to 84%. Regression analysis reveals that R 2 values, which represent the degree of control of driving pa- Y. Farhan respectively (where the F-value is significant at 0.1% and 0.5% levels). Such results imply that the height of local base level (m), and the mean height (m) are the only morphometric driving parameters which have significant control on HI values in the W. Wala watershed. High annual soil loss and sediment load estimated recently, denote that the catchment is highly susceptible to surface erosion at present. Hence, the present study, and the resultant information would help to plan for efficient soil and water conservation measures to reduce soil erosion rates, conserve water, and to control sediment into W. Wala dam.

Morphometric Analysis of Kito and Awetu Sub Basins Jimma, Ethiopia

“…Basin area (A) is the most significant parameter in morphometric analysis. The volume of water that can be generated from the drainage basin and form stream flow is directly related to the drainage basin area [19]. Kito and Awetu sub-basins cover an area of 113.21km 2 and 77.17km 2 respectively.…”

“…Basin length is measured along the principal channel from the outlet to the water divide. Many researchers applied [16] formula to compute basin length [9][10][11]19]. Basin length is an important parameter to compute other geometric (shape) parameters of the drainage basin.…”

“…The value of the bifurcation ratio reflects the relief and dissection of the drainage basin. The value of bifurcation ratio varies from 2 in flat or rolling drainage basin to 6 in mountain or hilly drainage basin where drainage network is highly distorted [19]. The hydrological response of drainage basin to rainfall is highly correlated with bifurcation ratio.…”

“…Different methods have been developed for morphometric analysis and applied in many river basins and sub-basins in different parts of the globe [4,[12][13][14][15][16][17][18]. Various scholars have carried out morphometric analysis of river basins by using RS and GIS techniques [19][20][21][22]. GIS and remote sensing techniques are efficient tools in analyzing morphometric characteristics of the drainage basin.…”

Prioritization of Promising Wadi Wala Watershed (Southern Jordan) Using GIS-Based Morphometric Analysis and Multivariate Statistics

“…Consequently, surface erosion rates are considerably high [75]. Nine sub-basins (39.2% of the total) (sub-basins nos.…”