Effects of di‐(2‐ethylhexyl) phthalate on microbial biomass carbon and microbial community structural diversity in a Mollisol

Summary One of the most common persistent organic pollutants is di‐(2‐ethylhexyl) phthalate ( DEHP ), which has caused considerable pollution in the Mollisols of agricultural areas in northeast China. This research investigates the effects of different concentrations of DEHP from 0 to 35 days on microbial biomass carbon ( MBC ) and structural diversity in the microbial community of Mollisols. The results indicated that contamination by DEHP of more than 20 mg kg −1 could clearly affect MBC and structural diversity of the microbial community of a Mollisol in a short time depending on the dose of DEHP . At concentrations of DEHP >20 mg kg −1 , we observed that the larger was the concentration of DEHP , the greater was the effect on the MBC and diversity of the soil microbial community. The DEHP concentration or incubation time had negative correlations with MBC , and the evenness ( E H ), Shannon ( H ) and richness ( S ) indices of the microbial community, and the DEHP concentration had a dominant effect on microbial properties. The dominant bacterium in the DEHP ‐contaminated soil was B acillus . Furthermore, bacterial community structure changed under different amounts of DEHP stress and with the increase in incubation time; Pseudomonas and Sphingopyxis clearly increased in number with large concentrations of DEHP . The change in the microbial population indicated that these two bacteria might have a strong resistance to change under the microbial DEHP stress. HighlightsDEHP significantly changed MBC and microbial diversity of a Mollisol. The change in MBC was related to the composition of the soil microbial community structure. DEHP had a persistent effect on the microbial community in a Mollisol. Bacillus were the dominant bacteria in the DEHP ‐contaminated soil.