Halophytes play important role in phytoremediation of salt-affected soils in the bed of Urmia Lake, Iran

Abstract

Soil salinity is a major threat in agriculture even in semi-arid regions of the world which can accelerate land degradation and desertification and decrease agricultural productivity and consequently jeopardize environmental and food security. Halophytes play important role in phytoremediation. This study is assessed the potential of Halocnemum strobilaceous, Atriplex verruciferae, Salsola crassae, and Salicornia europaeae in phytoremediation of saline soils occurred after water level desiccation of Urmia Lake. Three distances from the water body (500, 1000, and 1500 m) was selected for evaluating. Soils and plants were analyzed using standard methods. The mean values of salinity indices of the saline-sodic soil samples were identified as pH 8.6 and electrical conductivity (EC _e) 65.34 dS m ⁻¹, also sodium adsorption ratio (SAR), and exchangeable sodium percentage (ESP) were higher than 13 and 15%, respectively. The maximum soil exchangeable Na ⁺, K ⁺, and Ca ²⁺ concentrations (7200, 1900, and 1400 mg kg ⁻¹, respectively), also the concentrations of Mn ²⁺ (12.5 mg kg ⁻¹), Fe ²⁺ (5.5 mg kg ⁻¹), and Cu ²⁺ (1.5 mg kg ⁻¹), were significantly different at various distances. However, the highest amounts were obtained at 500 m. In addition the concentration of Fe ²⁺ (511.85 mg kg ⁻¹), Zn ²⁺ (99.97 mg kg ⁻¹), and Na ⁺ (25.65 mg kg ⁻¹) was the highest, especially in shoots. Furthermore, Salicornia and Halocnemum were more effective in salinity-remediation in comparison to other halophytes. The maximum dry matter (38%), protein (16%), and oil percentage (3.5%) were found in Salicornia, followed by Halocnemum. The findings indicated that salt-accumulating halophytes could be considered as the suggestions for phytoremediation saline soils and desalinating soil in arid and semi-arid regions.