Abstract
Background and aims
Fertilization is a critical management practice for improving soil fertility and increasing agricultural production. We still don't fully understand how biotic and abiotic variables interact with soil multifunctionality in the rhizosphere soil of legume-Gramineae mixtures following fertilization. Studies on the effects of fertilization on the bacterial composition of legume-Gramineae mixtures in particular geographical areas are scarce.
Methods
To tackle this matter, we set up five treatments: no fertilizer zone (CK, N0P0K0), nitrogen-phosphorus-potassium zone (NPK, N2P2K2), nitrogen-less zone (PK, N0P2K2), phosphorus-less zone (NK, N2P0K2), and potassium-less zone (NP, N2P2K0). The soil data were measured to assess the response mechanism of legume-Gramineae mixtures to fertilization management.
Results
The fertilization treatment resulted in a beneficial impact on the rhizosphere soil nutrients, enzyme activity, and biological characteristics, reaching the maximum under N2P2K2 treatment. The analysis of the bacterial community revealed that the oligotrophic taxa decreased primarily due to fertilizer addition, including Acidobacteria, and enhancing the copiotrophic taxa, such as Bacteroidetes and Proteobacteria, in the soil. Furthermore, according to FAPROTAX analysis, the results indicated variations in the function of the bacterial community in the rhizosphere soil of legumes and gramineae. Fertilization indirectly affected soil versatility by changing the diversity and composition of bacterial communities.
Conclusions
The bacterial community can be reshaped and the properties of the rhizosphere soil can be modified by different fertilization treatments, thus impacting the potential function of the bacterial community. This study has the potential to offer scientific guidance for the rational management of fertilization in legume-Gramineae mixtures.