Estimating the extent of water erosion in the Wadi Al-Rumaitha Basin, northeast of Al-Muthanna Governorate

The Wadi Rumaitha Basin is located astronomically between two latitudes (30° 39' 18" - 30° 29' 56") north, between two longitudes (45° 52' 4" - 45° 45' 10") east, with an area of (68.5) km2, located in the southern part of Iraq within the administrative borders of Al-Muthanna Governorate, which is characterized by a dry climate. The research aims to study and estimate the extent of water erosion in the Wadi Rumaitha basin, detect risks and conditions that affect the properties and quality of soil and land uses in the region, highlighting the role of natural characteristics affecting its activity, different types of water erosion prevail in the study area, between rain erosion, stream erosion, and gully erosion. The locations and areas of the basins of the river network and the stream, gully, and rain erosion network were determined, by adopting several criteria, including the Fournier equation to measure rain erosion, and the Bergsma 1982 equation (to measure the degree of stream and gully erosion, then, modeling the areas of spread of each of them, by the use of geographic information systems technology. It became clear through the research that the Fournier index in the stations of the study area reached (19.87, 21.66, 16.53), respectively, this indicates that the Wadi Rumaitha basin area falls within the range of weak rain erosion, while funicidal erosion included (4) cases limited to the range of high and very severe fluid erosion, gully erosion included (7) areas confined between the (very light and very high) ranges, and their geographical distribution varies in the basin lands.