Dataset on surface peat stoichiometry and physical properties in boreal forestry-drained peatlands in Finland, Natural Resources Institute Finland

Dataset on surface peat stoichiometry and physical properties in boreal forestry-drained peatlands in Finland
Creators: Larmola T, Anttila J, Alm J 
The dataset consists of peat properties in a subsample of 30 drained peatland forests in Finland selected from the permanent sample plots of the 8th National Forest Inventory (systematic sample of plots on drained peatland forests, e.g., Hotanen et al. 2006).  The subsample included equally different site types of forestry-drained peatlands of those parts of Finland where drainage for forestry is economically viable (Latitude 60-66 ºN, annual temperature sum > 750 dd). 
The site selection criteria were average peat layer thickness of over 20 cm, no clear-cut areas, site drained before 1995 and ditching had detectably altered hydrology or vegetation. Peat analyses Finnish Forest Research Institute (now Natural Resources Institute Finland) sampled peat cores with a box corer in 2002, samples were analysed for bulk density, archived and remaining samples at depths 20-30, 30-40 cm (total of 58) were analysed in 2021. 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 ℃. 
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, Turunen J, Laine-Petäjäkangas A, Ovaskainen J, Laatikainen M Dataset on surface peat stoichiometry and physical properties in boreal undrained peatlands in Finland, Natural Resources Institute Finland (Version 1) [Dataset]. Zenodo. doi.org/10.5281/zenodo.10068486
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 - Forestry-drained peatland (FDP) for all rows
ncoord - North coordinate (latitude), degrees.
depth - Sampling depth. 30: 20-30 cm, 40: 30-40cm, avg: average of both depths.
type - Site type classification according to the Finnish peatland site type system.
origin – Origin of the FDP site type at undrained state. 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
n - Number of samples. 2 for averages from both depths, 1 for all other rows.

References
Hotanen JP, Maltamo M, Reinikainen A (2006) Canopy stratification in peatland forests in Finland. Silva Fennica 40:53–82.
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.