Dataset of tree canopy structure, understory reflectance spectra and fractional cover in hemiboreal and temperate forest areas in Estonia and the Czech Republic

The dataset includes understory spectral reflectance factors at wavelengths of 350–2500 nm, fractional cover data of understory, forest inventory data, and data on the light availability at forest floor (diffuse non-interceptance, DIFN) and tree canopy structure (effective plant area index, PAIe) in hemiboreal and temperate forests in Europe. The data were collected near peak growing seasons 2019–2020 in situ in total of 31 forest stands in a hemiboreal study site in Estonia (13 stands: 58°17’N, 27°19’E), and temperate mountain (8 stands: 49°30′N, 18°32′E) and floodplain (10 stands: 48°41′N, 16°57′E) sites in the Czech Republic. The first spread sheet contains descriptions of the variables, second spread sheet the stand characteristics, and third the spectral data. Version history: This is Version 2 of the dataset, which was used, together with data from [3], in the study of Forsström et al. [1]. If using Version 2, please cite Forsström et al. [1, 2]. Version 1 had an indexing error that caused the spectral data to be in the wrong order. Do not use Version 1. We thank Daniel Schraik, Bijay Karki, Titta Majasalmi, ‪Petr Lukeš‬, Lucie Homolová, Mait Lang, Jan Pisek, Mihkel Kaha, and Lauri Korhonen for collaboration. Data collection and preparation was supported by the Academy of Finland [BOREALITY, grant number 286390; and DIMEBO, grant number 3323004]; and by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme [grant agreement No 771049]. The content reflects only the authors’ view and the Agency is not responsible for any use that may be made of the information it contains.‬‬‬‬‬‬‬‬ [1] Forsström, P.R., Hovi, A., Juola, J., Rautiainen, M., 2023. Links between light availability and spectral properties of forest floor in European forests. Agricultural and Forest Meteorology. doi:10.1016/j.agrformet.2023.109481 [2] Forsström, P.R, Hovi, A., Juola, J., Rautiainen, M., 2024. Dataset of tree canopy structure, understory reflectance spectra and fractional cover in hemiboreal and temperate forest areas in Estonia and the Czech Republic. Mendeley Data, V2. doi:10.17632/9dx32rszp8.2 [3] Forsström, P.R., Juola, J., Hovi, A., Rautiainen, M., 2024. Dataset of understory reflectance spectra and fractional cover in a boreal forest area in Finland. Mendeley Data, V3. doi:10.17632/2g9nkcdj53.3