Soil Compaction Exacerbates the Impact of Organic Matter Removal During Timber Harvesting

Résumé

Soil contains a diverse environment of microbes that are crucial in numerous chemical cycles such as carbon and nitrogen. These microbes aid in the decay of plants and animals as well as acting as carbon storage. Thus, the health of forests is greatly intertwined with the soil microbiome. Timber harvesting practices can result in the removal of organic matter (OM) and severe compaction of soil, potentially forever altering the soil microbial community. Using data collected by the Mohn group at the University of British Columbia (UBC) as part of the Long-Term Soil Productivity Study (LTSP), we aimed to investigate the long-term effect of soil compaction and OM removal on microbial diversity and abundance. Through analysis of microbial diversity and differential abundance, we found that soil compactness decreased diversity as more OM was removed. Furthermore, we found that during minimal OM removal, microbial diversity could withstand compaction; however, this resilience declined during more severe OM removal. Thus, we conclude that severe OM removal negatively influenced the diversity of microbes among different compaction levels.