Effect of Forest Fires on the Alpha and Beta Diversity of Soil Bacteria in Taiga Forests: Proliferation of Rare Species as Successional Pioneers

• Published in: Forests
• Main Authors: Zhichao Cheng, Song Wu, Hong Pan, Xinming Lu, Yongzhi Liu, Libin Yang
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2024
• Subjects: soil bacteria; taiga forests; fire-burnt site; community structure; rare species; Plant ecology; QK900-989; taiga
• Online Access: https://doi.org/10.3390/f15040606; https://doaj.org/article/e50bbe00d3a94984a7316177720fcf0c

Forest fires are among the most influential drivers of changes in forest soil bacterial diversity. Nevertheless, little is known regarding the effects of forest fires on maintaining the complex interactions that preserve forest ecosystem stability. Therefore, this study characterized alterations in soil bacterial community composition and diversity within taiga forests subjected to varying disturbance intensities. Particularly, this study examined the bacterial community within a Larix gmelinii fire-burnt site in Daxinganling, analyzing the changes in bacterial community structure and function across light, moderate, and heavy fire-burnt sites, as well as a control sample site, utilizing Illumina MiSeq technology. Through an assessment of bacterial community diversity and soil physicochemical properties (moisture content (MC), pH, microbial biomass carbon (MBC), organic carbon (SOC), total nitrogen (TN), available nitrogen (AN), available phosphorus (AP), and available potassium (AP)), we explored the influence of the soil microenvironment on the soil bacterial community structure at the burnt site under different disturbance intensities. Our findings demonstrated that (1) there was no significant change in the Chao index of soil bacteria in the burnt site under different disturbance intensities, whereas the Shannon index decreased significantly ( p < 0.05) and the Simpson index increased significantly ( p < 0.05) in the burnt site under light and moderate disturbance. (2) The relative abundance of dominant phyla, such as Proteobacteria, Proteobacteria, and Actinobacteriota, did not change significantly in the fire-burnt site under different disturbance intensities, whereas rare species, such as Acidipila , Occallatibacter , and Acidibacter , experienced a significant increase in relative abundance at the genus level. (3) The results of principal coordinates analysis (PCoA) and canonical correlation analysis (CCA) revealed significant differences in the Beta diversity of soil bacteria in the fire-burnt ...