Soil erosion risk assessment of the Lakhmess watershed (northwestern Tunisia) via the SEAGIS model: Inferred prioritization of risky sub-watersheds

• DOI: 10.1016/j.ijsrc.2024.08.001
• Publication Date: 2024-08-10T15:44:57Z
• Authors: Afef Marghmi; Lilia Ben Cheikha; Amina Mabrouk El ...; Moncef Gueddari
• Keywords: Siltation; WEPP

Water erosion in Tunisian semi-arid regions causes harmful effects by silting reservoirs and reducing agricultural lands soil fertility. Several factors are involved the process: rain erosivity, fragility, degraded land cover on steep slopes associated with intensification of inappropriate human practices. Thus, identifying vulnerable sub-watersheds based assessed loss rate is very important to apply suitable conservation measures. The current research aimed prioritize risky areas Lakhmess watershed, north-west Tunisia via Soil Erosion Assessment using Geographical Information System (SEAGIS) model. To sediment yield, covering an area 162 km2, was divided into 16 (L1–L16), according hydrographic network. Then, mean annual yield watershed were estimated integrating Revised Universal Loss Equation (RUSLE) Sediment Delivery Ratio (SDR) SEAGIS model their spatial distribution determined. obtained results indicate that average 4.2 t/ha/y 2.6 t/ha/y. Maner's SDR selected as best for estimating SY, standard error, deviation, coefficient variation values 0.75%, 0.01, 0.45%, respectively. prioritization reveals among sub-watersheds, three (L10, L12, L15) identified being a high priority class. these explained slope rainfall erosivity factor. Six (L2, L4, L5, L6, L7, L16) found belong low class, they characterized gentle slope, which appears be extremely determining These findings constitute basis decision makers plan effective measures conserve lands, soil, water resources northwestern Tunisia.