Sustainable use of salt-degraded and abandoned farms for forage production using halophytic grasses
Four halophytic perennial forage grass species, Distichlis spicata, Paspalum vaginatum, Sporobolus virginicus and S. arabicus, were planted in three salt-degraded and abandoned farms at Mezaira’a, Madinat Zayed and Ghayathi in the United Arab Emirates. The salinity of the irrigation water in the three farms at the time of establishment of the grasses ranged between 14.1 and 17.4 dSm–1. The productivity of the grasses was assessed over 3 years (2012–14) by harvesting three times per year. Averaged over locations and species, dry biomass yields of the four grasses ranged between 32.64 and 40.68 t ha–1 year–1. Sporobolus virginicus produced highest biomass yields, followed by D. spicata, P. vaginatum and S. arabicus, although differences among the four grasses were marginal. In Madinat Zayed and Ghayathi, the average respective forage yields in terms of water productivity were estimated to be 1.68 and 2.42 kg dry matterm–3 water, better than the reported yield of the traditionally cultivated Rhodes grass (Chloris gayana) from less saline conditions. The study showed that the four halophytic grasses have the potential to contribute to rationalised use of scarce water resources for forage production, besides providing options for enhancing domestic forage production through rehabilitating the salt-affected farms that are unproductive for conventional crops.