Sediment continued iron cycling

The cycle of iron solubilization will continue as long as bacteria and/or plants produce organic ligands.The cycle will stop when sulfate reduction rates are high and organic ligand production is low. At this point soluble hydrogen sulfide reacts with Fe(II) to form sulfide minerals. The iron cycle shown in Fig. 10.15 for salt marsh sediments may also occur in other marine sedimentary systems. 

AVT Barg BD BDHR BF BOF BOOM BOP BS W BSI BTA Btu/lb BW BWR BX CA CANDUR CDI CFH CFR CHA CHF CHZ Cl CIP CMC CMC CMC COC All-Volatile treatment bar (pressure), gravity blowdown blowdown and heat recovery system blast furnace basic oxygen furnace boiler build, own, operate, maintain balance of plant basic sediment and water British Standards Institution benzotriazole British thermal unit(s) per pound boiler water boiling water reactor base-exchange water softener cellulose acetate Canadian deuterium reactor continuous deionization critical heat flux Code of Federal Regulations cyclohexylamine critical heat-flux carbohydrazide cast iron boiler clean-in-place carboxymethylcellulose (sodium) carboxy-methylcellulose critical miscelle concentration cycle of concentration... 

Two remaining factors need to be considered in addressing the ultimate fate of arsenic within the sedimentary basins of Southeast Asia. First, arsenic, while cycled in the surface soils, is partially leached into deeper portions of the profile (i.e.. As is not conserved during the anaerobic cycle). Second, these basms are active and contmue to receive sediment loads, leading to continual burial of arsenic deeper in the soil profile. Once deeper in the soil, the cycling of iron, and hence the fate of arsenic, is altered. Dampened fluctuation in anaerobic-aerobic... 

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