Impact of sulfate and iron oxide on bacterial community dynamics in paddy soil under alternate watering conditions

Abstract

Sulfate and iron oxides are often used as amendments in paddy soil, but their ecological risks for soil microbiomes are not well understood. Paddy soil amended with gypsum or hematite was incubated in laboratory microcosms under submerged (56 d) and subsequent dry (35 d) conditions. The soil bacterial community composition stabilized after 15–21 d of submergence and remained largely unchanged after redrying. The presence of OTUs related to facultative anaerobic bacteria (mainly Acidobacteria groups 7 and 16, Gemmatimonas, and unclassified bacteria) probably accounted for the limited variation in community composition after redrying, as suggested by random forest regressions. Redrying caused ..