Science et changements planétaires / Sécheresse


Comparative study of saline soil reclamation under natural and irrigated conditions in a semiarid region Volume 14, issue 3, JUILLET-AOÛT-SEPTEMBRE 2003

Institut national de recherche du génie rural et des eaux et forêts, 17, rue Hédi Karray, BP n° 10, Ariana 2080, Tunisie <hachicha.mohamediresa.agrinet.tn> École nationale supérieure agronomique, Laboratoire de sciences du sol, 65, rue de St Brieuc, 35042 Rennes, France Institut national agronomique de Tunisie, Laboratoire de sciences du sol, 43, avenue Charles Nicole, 1082 Tunis Mahrajène, Tunisie.

Two examples of reclamation of soils affected by salt are compared. In the lunet of El Mabtouha, percolative reclamation occurred under natural conditions, fallow for two thousand years. In the perimeter of Kalaât Landelous, under hydro‐agriculture management for several years, reclamation took place within the pace of a few years, changing from a confined context to a seasonal percolative context following drainage action. The two schemes show many similarities. The desalinisation of the first 50 centimetres permitted agricultural use. Nature required two thousand years ; reclamation of salt‐affected soils by man was done in only a few years. In a semiarid region where soils are often lost by salinisation, reclamation offers one positive approach. But this reclamation remains fragile and dependent on the drainage network performance and on rainfall.