Response of fungal communities in different soils to biochar and chemical fertilizers under simulated rainfall conditions.

Biochar is a good soil additive, which cannot only effectively store carbon, but also improve soil fertility and crop yield. However, the specific response of fungal communities to biochar and chemical fertilizers are still relatively lacking. In addition, most studies do not take into account rainfall factors when conducting culture experiments. In the case of simulated rainfall, we investigated the response of fungal communities in different soils to biochar and fertilizers in China and analyzed the correlation between chemical properties and different fungal species. The tested soils were yellow-brown soil, fluvo-aquic soil, lou soil and black soil, and the simulated daily rainfall was 25 mm. The results indicated that the application of biochar and chemical fertilizers had a greater impact on the alpha diversity of acidic soils (yellow-brown soil, fluvo-aquic soil), but less on alkaline soils (lou soil, black soil). The relative abundance of Ascomycetes was most affected by biochar and fertilizer in any soil. From the point of view of the fungal community, yellow-brown soil was more suitable for single application of biochar, because it not only improved the ability of the soil to degrade persistent organic matter but also inhibited the spread of soil pathogens. In black soil, the relative abundance of Fusarium was significantly reduced by the combined application of biochar and chemical fertilizers (FC), and the decline was much higher than several other bacteria. However, FC caused the greatest changes in the structure of all soil fungal communities. Moreover, there was a significant correlation between the content of available nutrients and composition of fungal community in fluvo-aquic soil. In summary, it can be explained that the effects of biochar and chemical fertilizers on soil fungi may vary depending on the soil type, so it is very urgent to conduct long-term research on different typical soils.