Remediation of Brine-Contaminated Soils Using Atriplexspp. (Chenopodiaceae)

Abstract

The ability of some halophytes to accumulate salts may make them helpful in remediating soil contaminated with produced water and drilling mud from oil and gas exploration and production. Three inland halophytes, Atriplex acanthocarpa (two accessions) and A. canescens, were grown in pot culture in salt-contaminated soil, soil contaminated with salt and hydrocarbons, and uncontaminated soil collected from a Webb Co., Texas, gas production site. Electrical conductivity and soluble sodium of the soil extract were determined prior to planting and re-analyzed following harvest. Total sodium content in mature leaves was determined following harvest. Mature plant survival for all species in all soils ranged from 90–100%. In the salt-contaminated soil, post-harvest electrical conductivity and soluble sodium were significantly lower in the planted soils than in the unplanted soil. For each accession, biomass and plant mortality were greatest in the salt-contaminated soil. In both contaminated soils, the local ecotype of A. acanthocarpa had the highest concentration of tissue sodium and produced the greatest decrease in both electrical conductivity and soluble sodium. Field studies are necessary to determine the effectiveness of in situ application.

The effect of soil physical amendments on reclamation of a saline-sodic soil: simulation of salt leaching using HYDRUS-1D

“…Salt movement within soil profiles are also affected by climatic conditions as well as soil characteristics (Duan et al 2011). This is particularly important for the reclamation of land in arid and semi-arid environments with highly variable rainfall patterns, where an extended period of dry conditions can result in the upward movement of water and salt to the surface soil (Keyes et al 1999). Therefore, soil-climate interactions and their effect on salt movement (e.g., salt distribution and salt precipitation) have to be considered for the evaluation of salt leaching success and long-term soil reclamation.…”

Reclamation of Salt-Affected Land: A Review

“…The capillary rise, influenced by soil hydraulic parameters, determines the amount of solutes that can be transported [141,142]. Many salt-affected soils are located in (semi-)arid regions where leaching/irrigation is infeasible/limited and high evaporation rates may restore the saline impacts [132]. Therefore, seed germination in arid and semi-arid regions usually occurs after rainfall because of a reduction in the surface soil salinity [113].…”

“…Some genera of the Chenopodiaceae, including Atriplex, which are extremely salt tolerant, have been well studied for their revegetation and land reclamation potential [27,115,117,128]. The potential of Atriplex species for revegetation of salt-affected soils has been noted in several studies because of accumulation of salts in their aboveground tissues, particularly in their leaves [26,115,117,[129][130][131][132][133][134]. For example, Atriplex halimus accumulated up to 3137 meq kg −1 dry wt Na + in the shoot tissues after one year of planting [115].…”