NIRS spectra of fine roots from different plots of the Jena Experiment - Chen, Hongmei; Weigelt, Alexandra; Richter, Ronny (In supplement to: Elle, Oliver; Richter, Ronny; Vohland, Michael; Weigelt, Alexandra (2019): Fine root lignin content is well predictable with near-infrared spectroscopy. Scientific Reports, 9(1), 6396, https://doi.org/10.1038/s41598-019-42837-z, 2018)