DISCUSSION
Microbial biomass and functional diversity in different fertilizer treatments did not show significant
differences. The lack of significant differences in the microbial properties of the black soil was not
surprising owing to the following considerations: (i) the natural fertility of the black soil was relatively
high, and the application of chemical fertilizers did not result in any significant change in microbial
substrates (e.g., soil organic carbon), which thus did not result in significant changes in microbial biomass