Plant species for revegetation of a saline flue gas desulfurization sludge pond

Codisposing saline wastewater from electrical generating stations with flue gas desulfurization (FGD) scrubber sludge simplifies waste disposal but produces a saline waste that will later require revegetation. This waste is low in macronutrients, contains high levels of salts and B, and has a fine texture. This study identified plants, based on germination test results, that show promise for sowing at an evaporation pond in eastern Arizona where scrubber sludge and wastewater are codisposed. Forty-four grass, forb, and shrub accessions germinated on filter paper in saline water from the disposal pond. Dilutions of disposal pond water with untreated well water from the site ranged in EC from 0.17 to 3.03 S m^-1. Our criteria for evaluating plants to be used in revegetating saline FGD sludge were: (i) ability to germinate in increasing levels of disposal pond water and (ii) ease of establishment from seed. The percentage of pond water that would reduce germination to 50% that of well-water controls (P₅₀) ranged as high as >100 for the must tolerant plants. Accessions that show promise for sowing at these types of saline waste disposal sites include: Elytrigia pontica 'Jose' and 'Largo', Atriplex gardneri, Puccinellia airoides, P. distans 'Fults', Festuca arundinacea 'Alta' and 'Fawn', Krascheninnikoria lanata, Kochia prostrata 'Immigrant', Panicum virgatum 'Nebraska 28', Sporobolus airoides 'Saltalk', Leymus angustus 'Praireland' and Elymus trachycaulus 'Pryor'.