Organic Carbon transport model of abandoned river channels - A motif for floodplain geomorphology influencing biogeochemical swaying of arsenic

Meandering-river geomorphology, forming abandoned channels/lakes with organic carbon-burial and microbial reductive dissolution, play many crucial roles in controlling arsenic (As) fluxes sinks such as contaminated aquifers of riverine alluvial plains across the world. Suhiya oxbow-lake middle plain River Ganga, was selected natural laboratory. A top-down multidisciplinary approach chosen employing satellite imagery to analyse annual surface vegetation dynamics (Eichhornia Hydrilla). Side-scan sonar profiles two oxbow lakes along Ganga core data vintage topographical maps, estimated lake-sedimentation rate 9.6 cm/yr. Organic carbon [amino acids, aromatics, lingo-phenols lipids hydrocarbons] infiltration-based on hydrophobicity molecular-mass detected at different depths water sedimentary column. Elemental analysis showed lake groundwater As conc. varied from (0.37 185 ?g/l). diversity based study that large sized photoautotrophs Nostoc, Anabaena are replaced by Fe-oxido-reducing As-metabolizing bacteria e.g. Acidovorax, Dechloromonas enteric organisms Enterobacter, Salmonella bottom Based these inferences, a conceptual transport model constructed understand preferential preservation diagenesis resulting mobilization other geogenic elements.