Response of Soil Microbial Communities to Elevation Gradient in Central Subtropical Pinus taiwanensis and Pinus massoniana Forests

In forest ecosystems, elevation gradient is one of the most influential factors on soil characteristics, vegetation types, and soil microorganisms. However, it remains unclear how the elevation gradient and the soil environment under its influence affect soil microbial communities under two distinct vegetation types. In this study, high-throughput sequencing technology from Illumina was utilized to examine the response of soil microbial communities to elevation and their driving factors in forests of Pinus taiwanensis and Pinus massoniana in various Jiangxi Province locales. The results demonstrated that the elevation gradients of the two pines had significant effects on soil organic carbon (SOC) and total nitrogen (TN), both in unimodal mode as well as on the alpha diversity of soil microbes. The community structure of soil bacteria is more sensitive to elevation than that of soil fungus. At different elevations in the two pine forests, Acidobacteria, Proteobacteria, Chloroflexi, Verrucomicrobia, Bacteroidetes, Patescibacteria, and Thaumarchaeota are the dominant bacterial phyla, and Ascomycota, Basidiomycota, and Mucoromycota are the dominant fungal phyla. This investigation revealed that SOC and TN were the two most influential factors on the alteration of the soil microbial community in two pine forests. In summary, there were substantial changes in soil microbial diversity and community composition across the two different pine forests, with elevation and soil characteristics (SOC and TN) serving as the primary drivers.