Integration of soil erosion assessment methods using geographic information systems and remote sensing techniques

Soil erosion is a natural geological process but nowadays, it has become one of the most important environmental threats in the world. Unfortunately, the process has been accelerated due to human activities and climate change. The Mediterranean Basin is a region prone to erosion as climate change effects are already visible. Soil erosion is a threat to the economy of the developing countries that depend on agriculture such as Jordan. The purpose of this study is to estimate the soil erosion at Wadi Bin Hammad basin, examining the effect of factors on soil erosion, as well as comparing and verifying the measurement models, on a geographical area of 136.13 km2 located in the southern highlands of Karak, Jordan using Revised Universal Soil Loss Equation (RUSLE) and Soil and Water Assessment Tool (SWAT). The data input used for developing the model is collected from various sources, and the land cover data are prepared by examining both aerial photos and satellite images. RUSLE and SWAT maps were integrated by the GIS software application to create a final map to identify common areas affected by high erosion rates. By this way, accurate results can be achieved according to climate, morphology, geology, and hydrology. Similarly, the map will be used to accurately identify areas with high sedimentary production within the basin, for each sub-basin. The map will also be used in Jordanian mountain basins. Wadi Bin Hammad, achieved a mean value of 40.4 t ha-1 yr-1. The basin is classified according to erosion classes in the final map to five classes. The first class is the severe zone (81 - 100 t/h/y). It becomes clear that the severe zone of the erosion, covering more than 16.75% of the area, contributes 31.34% of soil loss from the basin in southeast Alqaser and northeast of Demna. The second class is the high zone (erosion between 41 - 80 t/h/y). The high erosion zone, covering more than 24.66% of the area, contributes 27.92% of soil loss from the basin in southeast Rakeen and Qaser. The third class is the moderate zone (erosion between 21 - 40 t/h/y). This zone, covering more than 29.03% of the area, contributes 24.36% of soil loss in the middle of the basin near Wadi bin Hammad village. The fourth class is the low zone (erosion between 11 - 20 t/h/y). The low erosion zone, covering more than 16.79% in the middle of the basin contributes only 12.30% soil loss. The final class is the very low zone (erosion between 0 - 10 t/h/y), which is estimated as 12.77% in the west of the basin in the Ghor near the Dead Sea contribute 3.99% soil loss. From the results of the spatial analysis between controlling factors and soil erosion; bare land, field cropland and high steep slope are all linked to extreme soil erosion.