Application of the SWAT model on the Medjerda river basin (Tunisia)

Abstract The Medjerda river basin (Northern Tunisia) is experiencing an intensification of agriculture and the irrigated area is increasing rapidly. The SWAT (Soil and Water Assessment Tool) model, a soil, water, sediment, and nutrient transformation and fate simulator for agricultural watersheds, was applied to this catchment to study the potential impact of land management scenarios. The model was able to represent the hydrological cycle even though some discrepancies were observed, probably due to a lack of sufficient rainfall data, and due to the lack of representation of reservoirs. It was predicted that converting all agricultural land to irrigated crop introduced significant changes on nitrate concentration in surface water. However, the concentration was still below the limit of potability. It was also predicted that drastic reduction in the load of ammonium and phosphorus could be achieved by collecting and treating wastewater from major urban areas.

[1]  Ben Abdelaziz Foued,et al.  Application of goal programming in a multi-objective reservoir operation model in Tunisia , 2001, Eur. J. Oper. Res..

[2]  Jeffrey G. Arnold,et al.  Formulation of a hybrid calibration approach for a physically based distributed model with NEXRAD data input , 2004 .

[3]  D. Faust,et al.  Sedimentation and soil formation phases in the Ghardimaou Basin (northern Tunisia) during the Holocene , 2002 .

[4]  Olivier Barreteau,et al.  What kind of water models are needed for the implementation of the European water framework directive? Examples from France , 2003 .

[5]  Fayçal Bouraoui,et al.  A long-term hydrological modelling of the Upper Guadiana river basin (Spain) , 2003 .

[6]  Joe T. Ritchie,et al.  Model for predicting evaporation from a row crop with incomplete cover , 1972 .

[7]  C. Priestley,et al.  On the Assessment of Surface Heat Flux and Evaporation Using Large-Scale Parameters , 1972 .

[8]  Jimmy R. Williams.  Sediment Routing for Agricultural Watersheds , 1975 .

[9]  J. Dørge,et al.  Implementation of the water framework directive – can we use models as a tool in integrated river basin management? , 2003 .

[10]  George C. Zalidis,et al.  Impacts of agricultural practices on soil and water quality in the Mediterranean region and proposed assessment methodology , 2002 .

[11]  A Mtimet,et al.  Soils of Tunisia , 2001 .

[12]  J. Nash,et al.  River flow forecasting through conceptual models part I — A discussion of principles☆ , 1970 .

[13]  John R. Williams,et al.  LARGE AREA HYDROLOGIC MODELING AND ASSESSMENT PART I: MODEL DEVELOPMENT 1 , 1998 .