Modelling soil erosion and sediment transport under different land management options in a Southern Italy watershed

The aim of the study is to investigate the influence of different land management options on the sediment load at the watershed scale. To reach this aim the Annualized AGricultural Non Point Source (AnnAGNPS) model was used in the Candelaro basin (2300 km2). The watershed is located in a semi-arid area of southern Italy (Puglia region) and is affected by extensive erosion processes on the hillslopes. The sediment transport simulations have been compared with 15 years (1970–1984) data coming from measures taken in two sub-watersheds (Vulgano and Salsola). Afterwards the model has been applied for a period of 24 years (1985–2008) to evaluate the effects of different land management options on the sediment yield: traditional best management practices (BMPs), environmentally-targeted agricultural practices and water and soil conservation works. The results obtained in the first part of the work show that AnnAGNPS model performs well in simulating runoff and sediment yields at the watershed scale. Furthermore the analysis carried out shows that the model is an efficient tool to assess the influence of different management options in the long term and in different weather conditions