The inadequate management of the irrigation water have caused salinity and sodicity problems in the irrigated perimeters with significant reduction of crop yields. This research was carried out in a greenhouse of CCA/UFPB, with the objective of studying the effects of necessity of the gypsum (NG): 0 and 40%, urban waste compost (CLU): 0 and 20 t ha-1 and periods of incubation with vinasse: 15, 30, 45 and 60 days, on the reclamation of a sodic soil, from the "São Gonçalo Irrigation Project", in the State of Paraiba, Brazil. The experiment was conducted in randomized block design in a 2 x 2 x 4 factorial scheme, with three repetitions and herbaceous cotton variety CNPA-7H as test crop. The treatments of gypsum + CLU increased the emergence percentage (%E), the dry matter (DM) and Ca2+ and decreased the levels of Na+ and pH of the leached solution, in relation to the soil incubated with vinasse, while Ca2+, increased with gypsum and decreased with CLU. For the incubation periods, there was linear reduction in Na+ contents in the presence of NG and CLU, isolated and when associated, there was also decrease of Ca2+ and of the electrical conductivity (CE) presenting quadratic effects and increase of the pH. The incubation periods only with vinasse increased the %E and the CE showing quadratic effect and reduced linearly, form the DM and the Ca2+.
exchangeable sodium; soil management; reclamation
