Evolu o da salinidade no solo sob cultivo de mel o irrigado com águas de diferentes salinidades

This study was conducted during August 21, 1998 to January 20, 1999, with the objective of determining the evolution of the soil salinity under melon during two cycles, irrigated with different depths of water of low and high salinity, in Mossoró, RN. The experimental design adopted consisted of radomized blocks in a 2 x 6 fatorial scheme, with 3 repetitions. Six irrigation depths (0.55, 0.70, 0.85, 1.00, 1.15, and 1.30 of maximim crop evapotranspiration - ETm) and two levels of salinity of the irrigation water (0.55 and 2.65 dS m-1) were analysed. In general the soil salinity tended to achieve equilibrium starting from the end of the first cycle. The salinity in the second crop cycle, increased in the deeper layers towords the end of the cycle, although the concentration of salts was higher is the superficial layer. In the first as well as in the second cycle, the mean salinity in the root zone reduced linearly with the irrigation depth.