SPRUCE: Sphagnum Phytobiome Responses to Whole Ecosystem Warming and Elevated Atmospheric CO2 in July, 2017-2021

Description

This data set reports the (1) C and N isotopic composition of Sphagnum moss tissue collected from inside the SPRUCE experimental study plots from 2019-2021, as well as (2) rates of nitrogen fixation and methane oxidation measured for Sphagnum from 2017, 2019, and 2021. Both (1) and (2) also contain measurements of Sphagnum tissue % water content. This dataset contains two files in comma-separate (*.csv) format. Investigations leveraged the SPRUCE experiment where air and peat warming were combined in WEW treatments. SPRUCE is located at the 8.1-ha S1 Bog forest site in northern Minnesota, 40 km north of Grand Rapids, in the USDA Forest Service Marcell Experimental Forest (MEF).

1. Sphagnum C and N concentrations and ¹³C and ¹⁵N isotopic natural abundance were determined for three replicate Sphagnum tissue samples collected from inside the SPRUCE enclosures in July 2019-2021. Elemental and isotope analyses were conducted at the University of Georgia – Center for Applied Isotope Studies (CAIS https://cais.uga.edu/). Plant elemental analysis was performed by the micro-Dumas method, while isotopic natural abundance was measured by isotope ratio mass spectrometry. ¹³C natural abundance is expressed as the per mille (‰) deviation from the Pee Dee Belemnite standard (PDB) ¹³C:¹²C ratio (δ¹³C), while ¹⁵N natural abundance is expressed as the ‰ deviation from the N₂ atmospheric ¹⁵N:¹⁴N ratio (δ¹⁵N).
2. Rates of nitrogen fixation and methane oxidation were measured using serum bottle incubations performed with Sphagnum collected inside the SPRUCE enclosures in July 2017, 2019, and 2021. Rates were calculated according to the amount of ¹⁵N-N₂ or ¹³C-CH₄ incorporated into the Sphagnum tissue or incubation headspace over the 48-hour incubation period. In 2017, incubations were performed in growth chambers set to the temperature of the experimental plots during Sphagnum sampling. In 2019 and 2021, the incubations were performed directly inside the experimental plots.

Citation

Petro, C, A Carrell, RM Wilson, K Duchesneau, S Noble-Kuchera, T Song, CM Iversen, J Childs, G Schwaner, J Chanton, RJ Norby, PJ Hanson, JB Glass, D Weston, JE Kostka.. 2023. SPRUCE Sphagnum Phytobiome Responses to Whole Ecosystem Warming and Elevated Atmospheric CO2 in July, 2017-2021. Oak Ridge National Laboratory, TES SFA, U.S. Department of Energy, Oak Ridge, Tennessee, U.S.A.
https://doi.org/10.25581/spruce.105/1924666.

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Friday, February 17, 2023

SPRUCE ID: spruce.105

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