Effects of Soybean Stover-Derived Biochar on Microbial Community and Structure in Loess Soil

Soil microorganisms play a crucial role in nutrient availability and overall soil health. However, the effects that biochar has on soil microbial communities are not well understood. This study analysed the effects of biochar pyrolysis temperature and application rate on the soil microbial community of loess. Two biochars derived from soybean stover were produced at 300 and 600°C (BC300 and BC600, respectively) and were applied to loess at the rates of 1, 3, and 5% (w/w). After fifteen weeks of incubation, soil microbial analysis was performed using 16S rDNA amplicon sequencing technology. All of the BC300 and BC600 treated soils were shown to have an increase in the relative abundance of Gemmatimonadetes and a decrease in Actinobacteria and Chloroflexi. Proteobacteria also showed a significant increase in the majority of the biochar treated soils. Biochar led to a shift in the soil microbial community and caused a significant increase in the relative abundance of bacteria from the genus Lysobacter. Based on the results of this study, soybean stover-derived biochar should be considered as a potential soil amendment for improving the health of loess or other soils in semi-arid climates.