MANAGEMENT OF SOIL EROSION AND SEDIMENT YIELD IN SEMI-ARID REGIONS, A CASE STUDY OF WADI SUDR WATERSHED, SOUTH SINAI, EGYPT

Controlling soil erosion and sediment yield is crucial for conserving soil and water resources. Although extensive research has examined this issue globally, the specific impacts of management practices on Wadi Sudr watershed have not yet been studied. This study aims to evaluate the impacts of mulching and check dam scenarios on sediment yield and soil erosion in Wadi Sudr, employing multi-regression analysis to forecast the percentage reductions achieved through these management practices. The Sediment Delivery Ratio (SDR) and Revised Universal Soil Loss Equation (RUSLE) models were integrated within ArcGIS to analyze sediment yield and soil erosion, examining the consequences of various recurrence intervals. Soil erosion was classified into five categories, ranging from severe to low. The most dominant category in Wadi Sudr is very low, covering 75% of the total area. The Al-Athamy sub-basin exhibited the highest soil erosion (17 t/ha/yr) and sediment yield (5.23 t/ha/yr) at the 100-year recurrence interval, prompting the implementation of management practices. Mulching with length ratios of 11,680 m, 25,980 m, and 32,320 m reduced soil erosion by 3%, 7%, and 9% and sediment yield by 19%, 23%, and 24%, respectively. Check dams though effective in reducing sediment yield by 35% and 86% for dams 1 and 2, minimally impacted soil erosion and were unsustainable and expensive. Results highlight mulching as the most cost-effective and sustainable management practice. These findings provide valuable insights for policymakers in developing effective soil and water conservation strategies to safeguard semi-arid watersheds.