Decomposition's effect of sulla residues (Hedysarum coronarium L.) on the chemical evolution characteristics of two soil's types under Tunisian arid climate [Effet de la décomposition des résidus de sulla (Hedysarum coronarium L.) sur l'évolution des caractéristiques chimiques de deux types de sol en climat aride Tunisien]

To investigate the potential of crop residues sulla (hedysarum coronarium l.) variety bikra 21,soil fertilization,the effect of its decomposition on the evolution of the chemical characteristics of clay and sandy soils of tunisia was evaluated by tracking incubation jars under natural conditions. the incubation was carried out under aerobic conditions and at a constant temperature of 28 °c during 90 days with moisture adjusted to 2/3 cc. carbon mineralization through the co2 released and the evolution of chemical soil parameters were observed at regular dates. sulla residues and soil texture influenced significantly (p <0.05) carbon mineralization and chemical soil parameters (cation exchange capacity cec,the sum of exchangeable bases,the saturation levels bases tsb),with higher for clay soils (cec =9.90 méq/ 100 g ; the sum of exchangeable bases = 10.43 méq/ 100 g;tsb=76 %) than in sandy soils values. the study showed that the residues of the fabaceae (sulla) are a source of organic matter that could be used in the fertilization of degraded soils tunisia.