Land amendment irrigation Phase III. Final Report. Santos-UQ Large core project.

Abstract

Intact soil cores from the Roma (QLD) area were irrigated with coal seam water. The soil was amended with gypsum and sulfur an irrigated with up to 100 mm coal seam water per week. Changes in soil solution composition, water infiltration and drainage water composition was investigated after every 100 mm of irrigation. To minimise salt accumulation in the soil, only soils with sufficient permeability (hydraulic conductivity) were suitable for coal seam water irrigation as salt could be leached from the soil during periods of high rainfall. The presence of a vegetation cover (Rhodes grass or lucerne) was necessary for maintaining soil surface structure and infiltration. As Rhodes grass is more salt tolerant, and tolerant of waterlogging, it is a more suitable pasture species for coal seam water