File name (ReadMe): ReadMe-Dataset Tilio-Acerion forests-Bo?, Slovenia This (ReadMe) file was created on 2026-01-23 by Lado Kutnar ------------------- GENERAL INFORMATION ------------------- Name of the dataset: Dataset on the topography, soil, vegetation and stand characteristics of Tilio-Acerion forests (Bo?, Slovenia) Authors Name and surname: Lado Kutnar ORCID: https://orcid.org/0000-0001-9785-1263 Institution/Affiliation: Slovenian Forestry Institute, Vecna pot 2, 1000 Ljubljana ROR organization identifier: https://ror.org/0232eqz57 Email: lado.kutnar@gozdis.si Name and surname: Anže Martin Pintar ORCID: https://orcid.org/0009-0007-6797-8045 Institution/Affiliation: Slovenian Forestry Institute, Vecna pot 2, 1000 Ljubljana ROR organization identifier: https://ror.org/0232eqz57 Email: anzemartin.pintar@gozdis.si Name and surname: Aleksander Marinšek ORCID: https://orcid.org/0000-0002-6190-9096 Institution/Affiliation: Slovenian Forestry Institute, Vecna pot 2, 1000 Ljubljana ROR organization identifier: https://ror.org/0232eqz57 Email: aleksander.marinsek@gozdis.si Name and surname: Janez Kermavnar ORCID: https://orcid.org/0000-0001-8052-4653 Institution/Affiliation: Slovenian Forestry Institute, Vecna pot 2, 1000 Ljubljana ROR organization identifier: https://ror.org/0232eqz57 Email: janez.kermavnar@gozdis.si Date of data collection: from 2021-03-01 to 2023-09-30 Geographical location of data collection: Bo?-Haloze-Dona?ka gora Natura 2000 site (code SI3000118), eastern Slovenia Information on the funders/programmes/projects that made the data collection possible: EU Project LIFE Integrated Project for Enhanced Management of Natura 2000 in Slovenia (LIFE17 IPE/SI/000011) Slovenian Research and Innovation Agency (ARIS), Research Program P4-0107 License: CC BY 4.0 DOI: https://doi.org/10.20315/Data.0016 ----------------------------- SHARING/ACCESSING INFORMATION ----------------------------- Data licences/restrictions: The data will be made available once the related paper has been published. Links to publications that cite or use the data: Not yet available Was the data obtained from another source? NO ---------------------- VIEWING DATA AND FILES ---------------------- File list: a) Explanatory variables_Tilio-Acerion forests: including 24 variables related to topography, forest stands and soils b) Vegetation variables_Tilio-Acerion forests: including 218 variables related to herb layer vegetation Additional related data collected that were not included in this dataset: NO Are there multiple versions of the dataset? NO -------------------------- METHODOLOGICAL INFORMATION -------------------------- Description of the methods used to collect/obtain the data: "a) Explanatory variables_Tilio-Acerion forests: On each plot, cover (%) of outcropping rock and rock fragments was recorded. Other topographic and site information were recorded as well, such as altitude (m above sea level), aspect (azimuth degrees) and slope (vertical degrees). Heat load index (HLI) or potential annual direct incident radiation was calculated using the formula published in McCune & Keon (2002) based on aspect, slope and latitude (i.e. equation no. 1). The location, diameter at breast height (DBH), and height of living trees, as well as the amount of dead biomass on each plot, were measured following the methodology of the Slovenian National Forest Inventory (Skudnik et. al, 2021; Skudnik et al., 2022; Pintar et al., 2024; Kutnar et al. 2025). Living trees and shrubs with a DBH of at least 10 cm were measured on circular plots of 200 m˛, and those with a DBH of at least 30 cm on 600 m˛ plots. For each tree, the azimuth and horizontal distance from the plot centre were recorded. The heights of at least five trees in each plot were measured (if more than one tree species was present, more than five tree heights were measured). Deadwood biomass (standing dead trees, lying dead trees, stumps, snags, and coarse woody debris) was also measured. Deadwood biomass with a DBH (standing dead trees, lying dead trees) or diameter (stumps, snags, and coarse woody debris) of at least 10 cm was recorded on circular plots of 200 m˛, and that with a DBH or diameter of at least 30 cm on 2,000 m˛ plots. For soil: We sampled organic (Ol, Of + Oh) layers and mineral parts of the soil up to a depth of 20 cm in two depths: from 0-10 cm and from 10 to 20 cm. On each plot, we systematically took sub-samples at three sampling points, which were evenly located 6 m from the centre of the plot. We combined the sub-samples from each horizon and depth into one composite sample. At each subsampling point in the mineral part of the soil, soil samples were also taken with Kopecky cylinders, with which we measure the bulk density. Soil analyses were carried out in accordance to standard procedures and protocols (ISO 10390:2006, ISO 10693:1995, ISO 11277:2009, ISO 11464:2006, ISO 11465:1993, ISO 13878:1998, ISO 1694: 1995). " b) Vegetation variables_Tilio-Acerion forests: The size of the sampling area was 400 m2 in all plots (Canullo et al., 2016). All vascular plant species in herb layer (all herbaceous species and woody individuals lower than 0.5 m) were recorded twice, in springtime (April 2022) and summer (June-August 2021 and 2022). The herb layer contains herbaceous (forbs, graminoids, ferns) and woody species (Canullo et al., 2016). The abundance of encountered species in herb layer was visually estimated using a modified Barkman scale (1964). Species nomenclature followed Tutin et al. (1964–1980, 1993) and Martin?i? et al. (2007). Data processing methods: Statistical analyses were computed with the R software (R Core Team, 2023). For the analysis of the vegetation data, spring and summer relevés were merged by choosing the higher cover values of both relevés. Species richness (total number of vascular plants in the herb layer) was modelled by fitting a series of 24 univariate generalized linear models. We assumed a Poisson distribution of errors, which is generally recommended for count data, and logarithmic link function was used in model specifications. Based on all significant predictors derived from univariate analysis, we carried out multivariate regression. Software information: R software version 4.3.0 (R Core Team, 2023) Standards and calibration data: "• ISO 11465:1993 Soil quality — determination of dry matter and water content on a mass basis — gravimetric method. • ISO 10693:1995 Soil quality — determination of carbonate content — volumetric method. • ISO 10694:1995 Soil quality — determination of organic and total carbon after dry combustion (elementary analysis). • ISO 13878:1998 Soil quality — determination of total nitrogen content by dry combustion (“elemental analysis”). • ISO 10390:2005 Soil quality — determination of pH. • ISO 11464:2006: Soil quality — Pre-treatment of samples for physico-chemical analysis. • ISO 11277:2009 Soil quality — determination of particle size distribution in mineral soil material — method by sieving and sedimentation." ------------------------------------- DATA-SPECIFIC INFORMATION: ------------------------------------- List of variables: a) Explanatory variables_Tilio-Acerion forests: Altitude Height above sea level (in m) Rockiness Cover of outcropping rock and rock fragments (in % of plot surface) HLI Heat load index (HLI) calculated with the equation no. 1 published in McCune & Keon (2002). T_COVER Cover of tree layer (%) (Canullo et al., 2016) H_COVER Cover of herb layer (%) (Canullo et al., 2016) Tree_N Number of different tree species in overstory (Borghi et al., 2024, Pintar et al., 2024) Height Mean height of overstory trees (m) (Tarmu et al., 2020) DBH Mean diameter at breast height (cm) of the 5 largest trees (Smy?ková et al., 2024) GS Total growing stock (volume) of all trees (Pintar et al., 2024) Acer Total growing stock (volume) of Acer pseudoplatanus and Acer platanoides (m3/ha) (Pintar et al., 2024) Fraxinus Growing stock (volume) of Fraxinus excelsior (m3/ha) (Pintar et al., 2024) Tilia Total growing stock (volume) of Tilia cordata and Tilia platyphyllos (m3/ha) (Pintar et al., 2024) Ulmus Growing stock (volume) of Ulmus glabra (m3/ha) (Pintar et al., 2024) Castanea Growing stock (volume) of Castanea sativa (m3/ha) (Pintar et al., 2024) Ostrya Growing stock (volume) of Ostrya carpinifolia (m3/ha) (Pintar et al., 2024) Carpinus Growing stock (volume) of Carpinus betulus (m3/ha) (Pintar et al., 2024) Tot_N Total number of living trees per hectare (Rybar et al., 2023) CE Clark and Evans Aggregation Index (Clark &Evans, 1954) DWD_V Total volume of deadwood biomass (m3/ha) DLR Dead-to-living tree growing stock volume ratio (Borghi et al., 2024) pH Soil reaction (pH) measured in 0,01M CaCl2 in 0–10 cm mineral soil layer C/N Ratio between carbon (C) and total nitrogen content (N) in 0–10 cm mineral soil layer CEC Cation exchange capacity (cmol(+)/kg) in 0–10 cm mineral soil layer BS Base Saturation (%) is calculated as follows: BS = Sum of Exchangeable Base Cations/CEC) x 100) in 0–10 cm mineral soil layer b) Vegetation variables_Tilio-Acerion forests: including 218 variables related to herb layer vegetation The herb layer contains 218 herbaceous (forbs, graminoids, ferns) and woody species followed Tutin et al. (1964–1980, 1993) and Martin?i? et al. (2007). The abundance of encountered species in herb layer was visually estimated using a modified Barkman scale (1964) and transformed in %.