Iron oxides promote physicochemical stabilization of carbon despite enhancing microbial activity in the rice rhizosphere

C stabilization mainly in 0.25-2 mm soil aggregates due to coprecipitation and aggregate formation with α-FeOOH. Moreover, Fe addition led to a dominance of Fe-oxidizing bacteria genera such as Pseudomonas, which fostered coprecipitation of Fe-OM formation. We highlight larger physicochemical stabilization of organic C by α-FeOOH addition despite raised hotspot area of microbial activity in the rice rhizosphere.