Abstract

Research found the effect of treated wastewater on chemical properties of the soil cultivated with cotton. The soil fertility was studied by using a randomized blocks experimental design in factorial scheme (4 x 2) with three replications, whose factors were four treated wastewater depths (278, 416, 554 and 692 mm) and two soil sampling times (before and after cultivation of colored cotton, with a rainfall of 89 mm during the crop cycle); while for the soil salinity, it was also used the experimental design in randomized blocks, but in factorial scheme (4 x 3) with three repetitions, being the factors the same four treated wastewater depths used in the fertility study, and three times of soil sampling (before and after the irrigation and after the rainfall period).  After irrigation with effluent of stabilization pond and a rainfall of 89 mm, the contents of P, K⁺, Ca²⁺, H⁺ and the capacity of cationic change of the soil increased, while the contents of Na⁺, Mg²⁺ and the sodium exchangeable percentage decreased. However, the electrical conductivity, the sodium adsorption ratio and the contents of calcium, magnesium, sodium, chlorides of the soil saturation extract decreased after five months of rains, which totalized 646 mm.

Key words: Reuse, irrigation, soil.