Halophytes as a Possible Alternative to Desalination Plants: Prospects of Recycling Saline Wastewater During Coal Seam Gas Operations

Large volumes of poor-quality water are generated by industries which need to be disposed of on a regular basis. While halophytes may be potentially suitable for this purpose, halophyte growth may be retarded by transient waterlogging associated with the application of large quantities of wastewater. The aim of this study was to assess the performance of two halophyte forage species, Atriplex halimus and Atriplex lentiformis, grown under different irrigation regimens, for a range of salinity concentrations. It was shown that Atriplex species can be successfully grown using high-salinity irrigation water (16 dS m⁻¹) and can handle a large quantity of water (800 mm year⁻¹ in addition to any natural rainfall), without any detrimental impact on plant growth and biomass production. Irrigation at 16 dS m⁻¹ resulted in an increase in soil salinity up to 12 dS m⁻¹, which was, however, still below the salinity of irrigation water. Given the fact that these salinity levels are considered to be optimal for halophyte growth, our data suggest a possibility of long-term use of large quantities of industrial-quality water without yield penalties. At least several more years of experimentation are needed to evaluate the environmental impact of this practice and before making recommendations to the industry.