Microorganisms play an important role in soil ecosystems, especially in
commercial rice paddy fields. However, it is not understood how organic
fertilizers affect microbial communities in these fields. In this study,
we used different long-term fertilization treatments (i.e., no
fertilizer, chemical fertilization, and 25% - 100% organic fertilizer)
to investigate their effects on soil fungal and archaeal communities,
rice yield, and soil physicochemical properties, and the interactions of
these indicators. The results showed that the organic replacement
treatments had a significant effect on the assembly of soil microbial
communities in rice fields, while different microbial taxa showed
different response patterns to the organic replacement treatments.
Species composition and community assembly process of fungal community
were more sensitive to the response of organic replacement treatment,
and alpha diversity of archaeal community was more sensitive to the
response of organic replacement treatment. OM, HN, Phosphatase, and TP
were the common soil indicators significantly associated with the three
microbial groups, among which OM was the most influential indicator in
this study. A total of 18 biomarkers were obtained by difference
analysis, distributed in Ascomycota, Basidiomycota and Chytridiomycota.
In addition, we obtained the keystones in the community through network
analysis and found that the organic replacement treatments affected the
microbial keystones by altering the soil HN and OM content, which in
turn led to the alteration of the soil microbial community. This study
provides new insights into the effects of different fertilization
regimes on soil bacterial, fungal and archaeal communities, and also
provides a theoretical basis for rational and balanced fertilization in
agricultural production.