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

Abstract

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 fi eld trials. The study used a culturedependent technique using Czapek agar (CZA) and De Man, Rogosa, and Sharpe (MRS) agar media combined with a modifi ed 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 fi eld 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.

Bio-organic fertilizers from food wastes induce changes in soil microbial community composition and the development of bok-choy (<i>Brassica rapa</i>)

“…4). This agrees with the results of a previous study (Dang et al, 2022a) and suggests a significant role of the lactobacilli community in soil respiration activities.…”

“…The measure of soil microbial respiration followed a procedure described in a previous study by Dang et al (2022a). In brief, soil samples were pre-dried naturally to constant weight before re-moisturization with sterilized water to 80%, measured with the soil tester.…”

“…The solution is considered saturated when all the KOH is converted into K 2 CO 3 , i.e., 10 ml of 0.5 M KOH is converted into 10 ml of 0.25 M K 2 CO 3 . The pH of the saturated solution is calculated at 11.83 according to the calculation described in a previous study (Dang et al, 2022a). At different time points, 1, 2, and 4 days, the pH of the KOH solutions in the beakers is measured using a pH meter (Hanna pH-211, Sigma-Aldrich, Germany).…”