Optical properties of Norway spruce needles

This dataset contains measurements of the optical properties (reflectance and transmittance) of Norway spruce (Picea abies) needles using the ASD FieldSpec 3 and 4 laboratory spectroradiometer and the ASD RST-3ZC integration sphere. Measurements of the optical properties were made on different locations in the Czech Republic and Finland (Šumava National Park 2009, Hyytiälä 2012, Bílý Kříž 2016, Geomon 2017 - several sites across Czech Republic). Some of the campaign datasets are further divided into several plots, sampled consistently for sun exposed parts of tree crowns and two age classes of needles (c0: current year needles, c1: one-year-old needles, in case of the Šumava 2009 dataset the c1 needles were not measured, therefore c2: two-years-old needles are included). The dataset allows the analysis of the geographical variability of the optical properties of Norway spruce between or within plots, as presented in Hovi et al., 2022 (https://doi.org/10.14214/sf.10683).