Assessing the Effect of Physicochemical Properties of Saline and Sodic Soil on Soil Microbial Communities

Soil physicochemical properties are the main driving factors affecting the stability and diversity of the soil microbial community. The impacts of the saline-alkali situation and associated soil degradation need to be understood and reversed as soil diversity and communities are increasingly affected by saline-alkaline soil. However, the differences between salinization and alkalization soil and their impact on microbiota have been overlooked. The object of this study is to demonstrate the differences in salinization and alkalization soil and the driving factors affecting microbiota. In this study, 12 soil samples collected from saline-alkaline spots were used to detect the differences in soil physicochemical properties. The soil microbial community was sequenced by high-throughput sequencing. The results of ESP and EC in the soil samples indicated that the soil samples were categorized as saline soil and sodic soil. Venn diagrams indicated that unique OTUs in saline soil showed higher adaptation and environmental tolerance. Partial Mantel tests showed that the differences in pH, exchangeable sodium percentage (ESP), C/N, Na, and K between saline and sodic soil were the primary determinants affecting the relative abundance of bacterial and fungal communities, besides electrical conductivity (EC). In the KEGG analysis, ESP mainly affected the cellular processes in the archaea. Metabolism in the bacterial function was positively correlated with K only in sodic soil. These results indicated that the proportions in sodic soil were more strongly affecting soil microbiota.

Automated summary

Soil physicochemical properties play a crucial role in determining the stability and diversity of soil microbial communities. The impacts of saline-alkali situation and soil degradation on soil diversity and microbial communities have been overlooked. This study aims to demonstrate the differences between saline and sodic soil and the factors driving the differences in microbiota. The results show that pH, ESP, C/N, Na, and K are the primary determinants affecting the relative abundance of bacterial and fungal communities. The proportions in sodic soil have a stronger impact on soil microbiota.