Dataset on surface peat stoichiometry and physical properties in boreal undrained peatlands in Finland, Natural Resources Institute Finland (Luke) and Geological Survey of Finland (GTK)

Dataset on surface peat stoichiometry and physical properties in boreal undrained peatlands in Finland 
Creators: Larmola T, Anttila J, Turunen J, Laine-Petäjäkangas A, Ovaskainen J, Laatikainen M 
The dataset consists of peat properties in a subset of 16 undrained peatland sites (32 peat samples) in Geological Survey of Finland (GTK) national peatland inventory. These sites were sampled between 2002 and 2017 and the subset selected from GTK peat sample archives. These 16 sites represented two pine-Sphagnum- dominated site types (IR, KR) and two treeless sedge fen types (VSN, RhSN) all in 4 replicates and sampled in 2 depths 20-40, 40-60cm). 
Peat analyses The peat samples were analyzed for C:H:N:S and ash concentration with Leco 628 CHNS analyzer following standard SFS EN13039 with FINAS accredited adjustments JOK3023. The dry matter content was analyzed after drying the sample at 105 ℃ and ash content based on loss on ignition at 550 ℃. The O concentration was determined by difference: %O = 100 - % (ash + total C + N + H + S).
Stoichiometric calculationsThe O concentration was determined by difference: %O = 100 - % (ash + total C + N + H + S). Atomic ratios of C:N, H:C and O:C were calculated based on the individual sample mass values. The C oxidation state (Cox), the oxidative ratio (OR), and the degree of unsaturation (DU) were calculated following equations in the study by Masiello et al. (2008). The analyses are described in more detail in Turunen et al. (manuscript). 
Related datasets used in the same publication are:
Larmola T, Anttila J, Alm J Dataset on surface peat stoichiometry and physical properties in boreal forestry-drained peatlands in Finland
Turunen J. (2023). Surface peat data, Geological Survey of Finland (Version 1) [Data set]. Zenodo. https://doi.org/10.5281/zenodo.8434148

Data column description 
ID - Site identifier
site - undrained peatland (UDP) for all rows
ncoord - North coordinate (latitude), degrees.
depth - Sampling depth. 20: 0-20 cm, 40: 20-40cm, 60: 40-60cm.
type - Site type classification according to the Finnish peatland site type system.
origin - UDP site type. I: treed peatland (peat typically Sphagnum-wood), II: treeless peatland (or sparsely treed, peat typically Sphagnum-sedge)
type_num - Nutrient level according to site type. 1 is the most nutrient rich and 4 is the least.
Cmol - Molar carbon concentration in the sample
Hmol - Molar hydrogen concentration in the sample
Nmol - Molar nitrogen concentration in the sample
Omol - Molar oxygen concentration in the sample
Smol - Molar sulphur concentration in the sample
bd - Bulk density, kg/m3
cox - C oxidation state
or - Oxidative ratio
du - Degree of unsaturation
hc - H:C ratio
cn - C:N ratio
oc - O:C ratio
References
Masiello CA, Gallagher ME, Randerson JT, Deco RM, Chadwick OA (2008) Evaluating two experimental approaches for measuring ecosystem carbon oxidation state and oxidative ratio, Journal of Geophysical Research 113, G03010, https://doi.org/10.1029/2007JG000534
Turunen J, Anttila J, Laine-Petäjäkangas A, Ovaskainen J, Laatikainen M, Alm J, Larmola T 2023. Impacts of forestry drainage on surface peat stoichiometry and physical properties in boreal peatlands in Finland. manuscript.