The Functional Biogeography of eDNA Metacommunities in the Post-Fire Landscape of the Angeles National Forest

Savanah Senn; Sharmodeep Bhattacharyya; Gerald Presley; Anne E Taylor; Bruce Nash; Ray A Enke; Karen B Barnard-Kubow; Jillian Ford; Brandon Jasinski; Yekaterina Badalova

doi:10.3390/microorganisms10061218

The Functional Biogeography of eDNA Metacommunities in the Post-Fire Landscape of the Angeles National Forest

Microorganisms. 2022 Jun 14;10(6):1218. doi: 10.3390/microorganisms10061218.

Authors

Savanah Senn^{1

2}, Sharmodeep Bhattacharyya^{2

3}, Gerald Presley^{2

4}, Anne E Taylor^{2

5}, Bruce Nash⁶, Ray A Enke⁷, Karen B Barnard-Kubow⁷, Jillian Ford¹, Brandon Jasinski¹, Yekaterina Badalova¹

Affiliations

¹ Department of Agriculture Sciences, Los Angeles Pierce College, 6201 Winnetka Avenue, PMB 553, Woodland Hills, CA 91304, USA.
² Environmental Sciences Graduate Program, Oregon State University, Corvallis, OR 97331, USA.
³ Department of Statistics, Oregon State University, Corvallis, OR 97331, USA.
⁴ Department of Wood Science & Engineering, Oregon State University, Corvallis, OR 97331, USA.
⁵ Department of Crop and Soil Sciences, Oregon State University, Corvallis, OR 97331, USA.
⁶ DNA Learning Center, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA.
⁷ Department of Biology, Center for Genome & Metagenome Studies, James Madison University, Harrisonburg, VA 22807, USA.

Abstract

Wildfires have continued to increase in frequency and severity in Southern California due in part to climate change. To gain a further understanding of microbial soil communities’ response to fire and functions that may enhance post-wildfire resilience, soil fungal and bacterial microbiomes were studied from different wildfire areas in the Gold Creek Preserve within the Angeles National Forest using 16S, FITS, 18S, 12S, PITS, and COI amplicon sequencing. Sequencing datasets from December 2020 and June 2021 samplings were analyzed using QIIME2, ranacapa, stats, vcd, EZBioCloud, and mixomics. Significant differences were found among bacterial and fungal taxa associated with different fire areas in the Gold Creek Preserve. There was evidence of seasonal shifts in the alpha diversity of the bacterial communities. In the sparse partial least squares analysis, there were strong associations (r > 0.8) between longitude, elevation, and a defined cluster of Amplicon Sequence Variants (ASVs). The Chi-square test revealed differences in fungi−bacteria (F:B) proportions between different trails (p = 2 × 10−16). sPLS results focused on a cluster of Green Trail samples with high elevation and longitude. Analysis revealed the cluster included the post-fire pioneer fungi Pyronema and Tremella. Chlorellales algae and possibly pathogenic Fusarium sequences were elevated. Bacterivorous Corallococcus, which secretes antimicrobials, and bacterivorous flagellate Spumella were associated with the cluster. There was functional redundancy in clusters that were differently composed but shared similar ecological functions. These results implied a set of traits for post-fire resiliency. These included photo-autotrophy, mineralization of pyrolyzed organic matter and aromatic/oily compounds, potential pathogenicity and parasitism, antimicrobials, and N-metabolism.

Keywords: DNA sequencing; functional diversity; molecular ecology.

Grants and funding

This work was supported by training and resources from the National Science Foundation IUSE grant, NSF DUE-1821657 awarded to Bruce Nash and Ray Enke in part to support Community College faculty. This material is based upon work supported by the National Science Foundation under Grant Nos. DBI-0735191, DBI-1265383, and DBI-1743442 which supported iPlant Collaborative and DNA Subway development.