In situ tracking of carbon flow through the soil microbiome
EMSL Project ID
50759
Abstract
Forest soils represent an environment with high carbon (C) stocks and important hotspots of C turnover and microorganisms are the most important actors in this process. The understanding of the C flow through the soil microbial foodweb would provide a baseline for the estimates of C balance under future climate scenarios. The aim of this proposal is to develop novel tools to track the speed of in situ C flow through various bacterial taxa and the comparison of the fate of the "easy" and "recalcitrant" C and to apply it to forest soils. In addition, we aim to assess the composition of bacterial communities involved in the utilization of recalcitrant C, exemplified by cellulose, and to identify the genes expressed to utilize this nutrient pool. Here we propose to achieve this by the combination of in situ 13C-Stable isotope probing, bacterial cell labelling and sorting, and subsequent application of nanoSIMS, amplicon sequencing and transcriptomics. Recent research shows that bacteria may be distinguished into "opportunists" utilizing easy C substrates (e.g., monosaccharides, amino acids, or organic acids) and "decomposers" that are able to access complex biopolymers (e.g., cellulose, hemicellulose, chitin). In certain bacterial classes, opportunists or decomposers tend to prevail. One of the aims of this proposal is to assign individual bacterial taxa into these groups. In addition to answering important questions of soil ecology, the project should establish novel experimental paths towards the tracking of organic matter turnover in the environment widely applicable to various ecological questions. If successful, the proposal will give us the best available estimate of the rate of C flow through the soil microbiome and its individual components for two substrates of differing complexity and helps to estimate, within selected taxonomic groups, the fraction of bacteria belonging into guilds with preference for decomposition / easy C utilization. Transcriptomics from sorted cells will indicate genes involved in C cycling and indicate why the taxa differ in nutritional preferences. Importantly, the project should demonstrate the utility of novel methodologies and their combination to the exploration of C flow in the ecosystem and make these methods available for future use across various systems.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2019-10-01
End Date
2022-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members