Transformation of organo-ferric peat colloids by a heterotrophic bacterium

摘要: Abstract Bacterial mineralization of allochthonous (soil) dissolved organic matter (DOM) in boreal waters governs the CO 2 flux from lakes and rivers to atmosphere, which is one main factor carbon balance high latitudes. However, fate colloidal trace element (TE) during bacterial processing DOM remains poorly constrained. We separated monoculture Pseudomonas saponiphila a creek allowed it react with Fe-rich peat leachate approximate (3 kDa–0.45 µm) composition C 1000 Fe 12 Al 3.3 Mg Ca 3.7 P 1.2 Mn 0.1 Ba 0.5 nutrient-free media. The total net decrease Dissolved Organic Carbon (DOC) concentration over 4 day exposure was within 5% initial value, whereas low molecular weight fraction org (LMW kDa ) yielded 16%-decrease due long-term bio-uptake or coagulation. There relative depletion 0.45 µm, LMW course interaction P. . Al, Mn, Ni, Cu, Ga, REEs, Y, U were mostly affected by presence exhibited essentially adsorption at cell surface first hours reaction, contrast Fe, Ti, Zr, Nb that showed both short-term removal physical coagulation/coprecipitation hydroxide. most TE 2–5 less microbial via than (HMW) fractions (