Fitorremediação de um neossolo flúvico sódico salino de Pernambuco com Atriplex nummularia Lindl

Abstract

Due to environmental and economic impacts of salinity and sodicity in soils, forms of recovery of theses soils contribute to improving the productivity and sustainability of farming systems and techniques for recovering theses soils is phytoremediation, using efficient plants at extracting of salts from soils. This study aims to evaluate the growth, production and extraction of salts by Atriplex nummularia grown on saline-sodic soil under water stress conditions, to compare soil properties before and after their cultivation, and to evaluate the osmotic potential of soil solution and morphoanatomy of vesicular cells accumulation of salts. The experiment was carried out in a greenhouse for 134 days, by growing Atriplex nummularia in pots with 20 kg of saline sodic with four levels of soil moisture (35, 55, 75 and 95% of field capacity) with a control (soil without plant). The experiment was performed in a randomized block with eight replications. The height, diameter and yield of dry leaf, stem and root were sensitive to soil moisture, and humidity corresponding to 75 and 95% of field capacity which resulted in better results. The vesicular cells of Atriplex nummularia were sensitive to variations in water content in soil. The variables of the exchangeable cations (Ca2+,Mg2+, K+, sum of bases) and total organic carbon remained stable between the beginning and end of the experiment in all treatments, while Na+ and exchangeable sodium percentage decreased after cultivation of the plant. In the soil solution the dynamics of the elements was evidenced by observing increases in Ca2+ Mg2+, Na+, Cl- and osmotic potential at the end of the cycle. The measurement of osmotic potential can be indicated as a good attribute for evaluating responses to treatments with hidric stress and saline water in plant and soil. The high concentrations of Ca2+, Mg2+, K+, and especially Na+ and Cl- in leaves of Atriplex nummularia, associated with high dry matter production characterizes this species as plant phytoextraction of salts.