Mapping and Quantification of Soil Erosion and Sediment Delivery in Poorly Developed Urban Areas: A Case Study

Abstract

Poorly developed regions in the Gaza Strip, Palestine, face significant risks to public safety, the environment, and stormwater infrastructure due to soil erosion and deposition. This study is the first of its kind to investigate soil erosion in this area. A revised universal soil loss equation (RUSLE) model was utilized and validated using field measurements of accumulated sediments at three major stormwater detention basins from 2014 to 2020. High-resolution maps were created to capture the urbanization effect and to further improve the future prediction of urbanization. The findings revealed that the highest potential for sediment generation in the Gaza governorate occurred over the slopes of the eastern ridge, which drain toward the city center. Sediment generation ranged from 1784 to 4281 ton/ha for the years of 2018 and 2020, respectively. The average sediment delivery ratio (SDR) was calculated to be 0.00134. The estimations for sediment export ranged from 0 to 135.3 ton/ha for the year 2020, with an average of 0.0737 ton/ha. The urban areas exhibited the least sediment export rate; however, the model revealed abnormal behavior for a dataset of the field measurements which was ascribed to the impact of destruction/reconstruction activities in the corresponded watersheds that followed the war in 2014. This conducted research stands as a pioneering effort in quantifying and cartographically representing sediment erosion potential within the Gaza Strip. Thus, it serves as an indispensable point of reference for future researchers in terms of the employed parameterization and calibration methodology. Furthermore, it holds distinct significance as an unparalleled resource for experts and stakeholders who are invested in comprehending the ramifications of erosion on urban landscapes and drainage systems.