Data from: Microbial activity contributes to spatial heterogeneity of wetland methane fluxes
Data files
Sep 14, 2023 version files 35.82 KB
-
all_data.csv
33.44 KB
-
README.md
2.38 KB
Abstract
The emission of methane from wetlands is spatially heterogeneous, as concurrently measured surface fluxes can vary by orders of magnitude within the span of a few meters. Despite extensive study and the climatic significance of these greenhouse gas emissions, it remains unclear what drives these large within-site variations, creating a knowledge-gap that impedes a mechanistic understanding of wetland fluxes. While geophysical variables including water table depth (WTD) and soil temperature are known to correlate with CH4 flux, measurable variance in these parameters declines as spatial and temporal scales become finer. Here, we leveraged depth-stratified gene abundance and gene expression measurements of methanogenesis and methanotrophy to investigate CH4 flux variance at an ombrotrophic peat bog. Our results show that the flux variance was strongly correlated to methanogen abundance and that peat depth also exerted significant control over CH4 flux, methanogen abundance, and the relationship between the two. Correlations between CH4 flux and either WTD or soil temperature were absent or minimal. These findings suggest that microbial factors likely underlie localized variance in wetland CH4 flux, and that a greater reliance on biological predictors could improve our ability to understand wetland methane fluxes at finer scales than is currently possible.
The majority of the data consists of RNA and DNA abundances of specific genes (mcrA, pmoA, mmoX) quantified via the digital droplet polymerase chain reaction (ddPCR) method. Relatedly, dsDNA abundance for corresponding samples were quantified using fluorometric methods on a Qubit. Additionally, there is accompanying environemntal data from the study site, including soil temperature (measure via in-ground probe), water table depth (measured from surface using constructed wells), and refusal depth (measured as a distance with an in-ground depth probe). Ferrous iron, total iron, and dissolved oxygen concenreated using Hach kits. Lastly, there is methane flux data for our study site, quantified via cavity ring down spectroscopy using a closed chamber method. All data has been processed in R Studio, using the packages specified in the accompanying manuscript.
Description of the Data and file structure
CSV with raw data:
- Identity: Refers to a unique sample location at the field site
- Time.Period: Refers to which sampling campaign sample was collected during
- Depth: Sample depth from surface (inches)
- Extraction.Mass.g: Mass used for nucleic acid extraction (g)
- qubit_RNA: RNA concentration in eluant (ng/ul)
- qubit_DNA: DNA concentration in eluant (ng/ul)
- Peat_depth: refusal depth for sample location (feet)
- flux_level: Classification of plot as high or low-fluxing site
- Soil_temp: Soil temperature (C)
- WTD: Water table depth (cm from surface)
- Flux: methane flux in ug/m2/hr
- Reco: CO2 flux in mg/m2/hr
- Fe_2_6: ferrous iron at 6” from surface (mg/l)
- Fe_2_12: ferrous iron at 12” from surface (mg/l)
- Fe_2_18: ferrous iron at 18” from surface (mg/l)
- Fe_T_6: total iron at 6” from surface (mg/l)
- Fe_T_12: total iron at 12” from surface (mg/l)
- Fe_T_18: total iron at 6” from surface (mg/l)
- DO_6: dissolved oxygen 6” from surface (mg/l)
- DO_12: dissolved oxygen 12” from surface (mg/l)
- DO_18: dissolved oxygen 18” from surface (mg/l)
- mcrA_full_norm: gene count of mcrA RNA
- pmoA_full_norm: gene count of pmoA RNA
- mmoX_full_norm: gene count of mmoX RNA
- mcrA_DNA_full_norm: gene count of mcrA DNA
- pmoA_DNA_full_norm: gene count of pmoA DNA
- mmoX_DNA_full_norm: gene count of mmoX DNA
The majority of the data consists of RNA and DNA abundances of specific genes (mcrA, pmoA, mmoX) quantified via the digital droplet polymerase chain reaction (ddPCR) method. Relatedly, dsDNA abundance for corresponding samples was quantified using fluorometric methods on a Qubit. Additionally, there is accompanying environmental data from the study site, including soil temperature (measured via in-ground probe), water table depth (measured from surface using constructed wells), and refusal depth (measured as a distance with an in-ground depth probe). Lastly, there is methane flux data for our study site, quantified via cavity ring-down spectroscopy using a closed chamber method. All data has been processed in R Studio, using the packages specified in the accompanying manuscript.
All datafiles can be opened in Excel or an equivalent CSV editor. The main script is in the form of an R markdown document.