Influence of Tree Vegetation on Soil Microbial Communities in Temperate Forests and Their Potential as a Proactive Indicator of Vegetation Shift Due to Climate Change

Unexpected vegetation shift is a serious problem caused by climate change, resulting in considerable damage to local communities. It is necessary to be continuously monitored, and the soil microbial community is expected to reflect the pressure on forest ecosystems due to climate change. We investigated soil bacterial and fungal communities in Odaesan at a four-year interval through eDNA meta-barcoding and analyzed the compositional and functional differences between forest types (Mongolian oak ( Quercus mongolica ) forest with and without Manchurian firs ( Abies holophylla )) and sampling years. As a result, denitrifiers predominated in the presence of Manchurian firs, but there was no difference in the influence of climate change by forest type. Although tree vegetation remained stable, the microbial communities significantly changed over four years. This result demonstrates that climate change significantly shifts the microbial communities, even if not enough to trigger a vegetation shift, thus a microbial indicator can be developed to assess the press disturbance accumulated on the forest ecosystem. Through this study, we identified the influence of Manchurian firs and that of climate change on soil microbial communities in temperate forests and demonstrated the potential of the microbial community as a proactive indicator of vegetation shift due to climate change.