المخاطر الجيومورفولوجية للسيول و أثرها في تغير الفئات الانحدارية لمناطق شرق العراق لمحافظتي واسط – و العمارة (دراسة حالة)‎

الملخص EN

The objective of this study is to determine the geomorphological risks of the floods and their effect on changing the slope categories of the eastern regions of Iraq within Wassit and Maysan governorates.

The study investigated the slope characteristics of the gradients and their trends, (ARC GIS 10.4), employing application programs and using topographic maps of the survey area (100000: 1).

The applied equations were used to extract the intensity of water erosion and the size of erosion through application Equation (Douglass) and (Fournier) and equation (Bergsma) for Rift erosion (2000) and the SRTM (2014) model, which obtained the model of digital elevation by means of US satellite data.

Comparison of the regression maps extracted from the two previous models shows that there is a clear variation between the categories.

The category (0-1, 9), which occupies an area of 25451.42 km2, is highlighted in the figure (flat surface) using the model (1996, GTOPO30) Using the SRTM model, it was found to be between 0-1.9, occupying an area of 32, 614, 43 km2, G in the flat surface It is clear from the difference in area that the heterogeneity between the surface and the high-level areas is apparent.

The study area includes Wasit and Amara Governorates, which are part of the flood plain, which are located between the latitude (00 00-00 40 33 North) and the longitude (10, 956.7 m).

The area was characterized by varying degrees of regression according to Zink classification.

Ranged between flat areas with a flat surface (0-1.9) to mountainous regions, With a high score of (more than 30)degree The direction of the gradient was determined as the trend of the south-east reached an area of 9779.81 km2 and 28.84% .

The river levels reached 7 levels and were used to extract the amount of erosion.

The water erosion was calculated by applying the equation (Doklas) and reached the highest limit in the station Badra up to (5, 8), which is high value of the size of erosion, and applied the equation Vorneh for the evaluation of the severity of the tariff, as above in the station Badra (40.1 m / km 2), While the study area was divided according to the law (Bergsma) to five degrees and it was determined that the degree of erosion of the fourth very high-scale is prevailing within the The area of the study is 17979, 74 km2, hence the reciprocal relationship between the slope categories, water erosion and the intensity of the floods