Effects of biochar addition on fungal communities: Implications for forest insects

Abstract

Many western forests are severely overstocked, creating a critical need to understand how forests can be thinned while maintaining biodiversity and other ecosystem services, such as carbon sequestration. Wood-inhabiting fungi play a critical role in carbon cycling and carbon sequestration. However, the effects of different management techniques on wood-inhabiting fungal communities have rarely been investigated. Here, we implemented a manipulative experimental design to determine the effects of thinning on fungal communities, with four levels of slash retention as well as four combinations of compensatory soil amendments (non-amended control, biochar, fertilizer, or fertilizer+biochar). We sampled our treatment plots for three years using above- and below-ground wood stakes (pine and aspen) and also conducted annual surveys of woody material for fungal fruiting bodies. Fruiting bodies were identified using a combination of morphology and DNA sequencing, while high-throughput DNA sequencing was used to identify fungi that colonized the wood stakes. Although differences in diversity and richness of fruiting bodies were not observed across treatments, the different levels of slash retention did affect the community composition of wood-inhabiting fungi observed as fruiting bodies. In contrast, the DNA-based survey of wood-colonizing fungi indicated that fungal communities were sensitive to levels of slash retention as well as different soil amendments, including biochar addition. Future work will determine how these changes in the fungal community may affect decomposition rates and explore how changes in the fungal community may affect other organismal groups, such as the many forest insects that interact with fungi.

Citation

Draeger, Kymberly R.; Lindner, Daniel L.; Jusino, Michelle A.; Page-Dumroese, Deborah S.; Palmer, Jonathan M.; Banik, Mark T. 2022. Effects of biochar addition on fungal communities: Implications for forest insects. In: Arango, Rachel A.; Pureswan, Deepa S., eds. 2022. Proceedings of the 7th North American Forest Insect Work Conference; Shaping Forests: Action in a Changing World. FHAAST-2022-01. Washington, DC: U.S. Department of Agriculture, Forest Service, Forest Health Assessment and Applied Sciences Team. p. 156-160.