A dataset of stem reflectance spectra for standing dead Scots pine trees
The methods used to collect and preprocess this dataset have been reported in detail in Juola J., Hovi A., Rautiainen M., 2022. A spectral analysis of stem bark for boreal and temperate tree species. Ecology and Evolution. DOI:10.1002/ece3.8718 The dataset includes stem reflectance spectra of standing dead trees for the species of Scots pine (Pinus sylvestris L.). We measured hemispherical-directional reflectance factors (HDRF) of stem samples. The data were measured using a Specim IQ imaging spectrometer. The measurements were taken from the northern side of the stem at breast height (1.3 m), and the image acquisition distance was 20 cm. The imaging spectrometer operates in the visible and near-infrared wavelength region (400–1000 nm). The measurements were made in the municipality of Rovaniemi, Finland. We measured 13 standing dead Scots pine trees, accounting to a total of 13 unique stem samples. One sample refers to a hyperspectral reflectance image taken of a single standing dead tree stem (at 1.3 m height). The 13 mean spectral signatures (presented in this dataset) were calculated for each sample by averaging the HDRF values over all pixels per wavelength. The measurements were conducted in the beginning of August 2022. All measurements were made under diffuse illumination conditions and the images were taken in perpendicular view-angle to the standing stem. The dataset includes 1) one tabular file that contains all 13 mean reflectance spectra, and 2) a supportive document that has images of the individual standing dead trees and RGB visualizations of the measured hyperspectral reflectance images. The spreadsheet (.csv) is organized as follows: first two rows that start with hashtag (#) contain comments for citing, first column "tree_species" (standing_dead_tree_pinus_sylvestris) indicates the standing dead tree species, second column "id" (K1-K13) indicates the unique stem id's for which images can be found in the supportive document, and the subsequent columns "wl397.32"-"wl1003.58" indicate the measured HDRF value at that wavelength. The encoding of the csv file is UTF-8. The supportive document (.pdf) contains the dataset description given here, but also images of the standing dead trees taken in the forest and their corresponding RGB visualizations of the measured hyperspectral reflectance images. The Diameter at Breast Height (DBH) are given for each stem in the figure descriptions. If you use this dataset, please cite: Juola, J., Rautiainen, M., 2022. A dataset of standing dead tree stem reflectance spectra for Scots pine. Mendeley Data, V1, doi: 10.17632/8dvx3vvvk9.1 Funding: Academy of Finland (ARTISDIG, grant number: 348152) Acknowledgments: We thank Veli Juola and Erkki Tuovinen for assistance in the field campaign.
Steps to reproduce
For the methods, see Juola J., Hovi A., Rautiainen M., 2022. A spectral analysis of stem bark for boreal and temperate tree species. Ecology and Evolution. DOI:10.1002/ece3.8718