This paper summarises some of the findings over the last four years on the effect of elevated sulfate concentrations as a result of salinisation on the soils in the Murray Darling Basin. The distribution, formation and some of the main properties of sulfidic soils in the Murray-Darling Basin will be addressed here.The data presented here indicates that we need to examine and take into account the important roles and major impacts that individual components of salinity, in this case sulfate, can have on the ecology of our inland regions.