Geochemical interactions between iron and phenolics originated from peatland in Hani, China: implications for effective transport of iron from terrestrial systems to marine

摘要: Iron is a restrictive element for primary productivity in the oceans. The influence of dissolved organic matters as metal chelators on bio-available iron input to ocean has been widely reported. However, natural matters, especially phenolics originated from peatlands and geochemical interactions with remains poorly understood. In this study, solid phase extraction-high performance liquid chromatography experiments were conducted determine vertical distributions phenolic acids different peat layers Hani Peatland, China. Ten acids, including protocatechuic acid, p-hydroxybenzoic gentisic caffeic etc. detected. Simulation phenolics-Fe under alkaline conditions (pH = 8.0 ± 0.1) indicated bearing either catechol or galloyl groups (such acid gallic acid) could chelate produce relatively stable complexes therefore help weaken its precipitation oxidative condition. addition, simulation artificial coastal waters demonstrated that complexation ensure at least 25 % initial Fe load dissolve water, implying large part rivers draining be transported through estuarine zones. Considering wide distribution globally, higher concentration peatlands, enhancement marine organisms by Fe, between are important significance transport terrestrial system