Compositional shifts in microbial communities in soils supplemented with iron oxide materials and inorganic fertilizer

Soil microbial communities play an important role in determining soil ecosystem health. However, the effect of chemicals added to the soil on the function and composition of the soil microbiome is not well known. This study evaluated the effects of magnetite materials and inorganic fertilizer on the microbial communities in the soils of both laboratory and field trials. The study used a culture-dependent technique using Czapek agar (CZA) and De Man, Rogosa, and Sharpe (MRS) agar media combined with a modified method for the assessment of soil microbial respiration to account for changes in the microbial community. Results performed with commercial vegetable soil in the laboratory and soils obtained from the field trial both showed an increase in soil respiration rates over time in response to fertilizer and iron oxide materials added to the soil. The iron oxide materials have been shown to have a stronger impact on the soil microbial communities compared to the fertilizer. In addition, the microbial population cultured on the MRS medium was considered to have an important role in total soil respiration. Further studies on the roles of different microbial communities in the soil as well as the combination of different analytical methods should be needed to improve our understanding of the relationship between soil microbial communities and changes in environmental conditions.