Recuperação de solo salino-sódico por fitorremediação com Atriplex nummularia ou aplicação de gesso.

Abstract

Arid and semi-arid environments may present salty soils, which hamper plant growth, being removed from productive process constituting degradation cores. Under these conditions, glycophyte plants can’t growth because high levels of salts hinder their metabolism, however, for halophytes this is favorable environment and these plants may represent a key to soil reclamation, extracting salts in the vegetable material produced by phytoremediation technique. The study was conducted in a saline sodic INCEPTISOL from the Cachoeira II Irrigation Perimeter, Serra Talhada (PE), with the objective of evaluating changes in soil physical and chemical properties when under cultivation with the halophyte Atriplex nummularia Lindl, compared with chemical correction with gypsum, and plant growth and production monitoring under two spacing in the pruning management every six months. Samples were taken every six months, with four soil samples (0, 6, 12 and 18 months) and three cuts in the plant 50 cm from the ground surface (6, 12 and 18 months) measuring the material produced at each pruning.The experimental design was randomized blocks, four treatments were evaluated: control (no soil management), chemical correction with gypsum (no crop) and two Atriplex nummularia cultivation, one at 1 x 1 m spacing and other at 2 x 2 m spacing, with four replications. The results of soil chemical and physical analysis revealed the contribution of gypsum application and especially the cultivation of atriplex plants in reducing the problems of salinity-sodicity and improving soil physical properties. The biometric analysis and plant tissue showed the Atriplex nummularia potential for phytoremediation, with emphasis on the 1 x 1 m spacing which presented as the best recommendation of cultivation with frequent pruning due to higher plant material yield and extraction of salt per planted area.