Mineralogy and hydrochemical characteristics of the late marshes and swamps of Hor Al Hammar, Southern Iraq

This study presents unpublished results on the hydrochemical characteristics of swamps (Hor) of Al Hammar, which could be useful for the intended restoration efforts. Electric conductivity and total dissolved solid values show that the investigated water is slightly brackish, due to the effect of evaporation and slightly acidic due to organic and biological activities producing sulfuric acid. Major cations and anions arranged according to their decreasing concentrations were: Na1+>Mg2+>Ca2+>K1+; Cl1−>SO42−>HCO31−. Hydrochemically the water of Hor Al-Harmmar can be classified as: Ca2+–Mg2+–Na1+–SO42−–Cl1− type. The study found that upon a continuous evaporation gradient, the water tended to approach the seawater type. Ion concentrations, except for Ca2+, increased towards the middle part of the Hor (Al-Shafi) and are explained as evaporative concentrations. The different behavior of calcium may be explained by the consumption of calcium sulfate by the organisms living in the Hor to build up their shells and skeletons. Factors affecting the hydrochemistry of the water of the Southern Iraqi swamp include the effect of seawater, weathering of soil and rocks, evaporation, biological activity, chemical precipitation of calcium carbonate, and the effect of clay minerals in the investigated water. The reported results could serve as background information needed for restoration of the marshland and swamp of Southern Iraq.