Revealing the transfer pathways of cyanobacterial-fixed N into the boreal forest through the feather-moss microbiome.

ABSTRACT:

Introduction

Biological N₂ fixation in feather-mosses is one of the largest inputs of new nitrogen (N) to boreal forest ecosystems; however, revealing the fate of newly fixed N within the bryosphere (i.e. bryophytes and their associated organisms) remains uncertain.

Methods

Herein, we combined ¹⁵N tracers, high resolution secondary ion mass-spectrometry (NanoSIMS) and a molecular survey of bacterial, fungal and diazotrophic communities, to determine the origin and transfer pathways of newly fixed N₂ within feather-moss (Pleurozium schreberi) and its associated microbiome.

Results

NanoSIMS images reveal that newly fixed N₂, derived from cyanobacteria, is incorporated into moss tissues and associated bacteria, fungi and micro-algae.

Discussion

These images demonstrate that previous assumptions that newly fixed N₂ is sequestered into moss tissue and only released by decomposition are not correct. We provide the first empirical evidence of new pathways for N₂ fixed in feather-mosses to enter the boreal forest ecosystem (i.e. through its microbiome) and discuss the implications for wider ecosystem function.

SUBMITTER: Arroniz-Crespo M 

PROVIDER: S-EPMC9780503 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature