Vis-NIR spectral data and chemical properties of humus samples from forest soils in Saxony

The data set consists of 360 samples and contains chemical properties important for humus assessment (pH value, cation exchange capacity, base saturation, C and N content, C/N ratio) as well as spectral absorbance data in the visual and near-infrared range of the electromagnetic spectrum of forest soil samples in Saxony. One part of the samples was collected during the German National Forest Soil Inventory (BZE). Sample acquisition took place in 2006, 2012 and 2014. The data set is supplemented with additional sample points from three test sites representing typical natural areas of Saxony (Wellbrock et. al, 2015, doi:10.3220/REP1449838842000). Data collection was performed using a satellite sampling scheme with eight satellites per point. The data set contains samples from both Oh-horizon and the five cm of the uppermost layer of mineral soil (Ah-horizon). Samples were dried at 40° (0-5 cm) and 60 °(Oh). The dry samples were sieved with a 2 mm mesh, homogenizing the material. All chemical analysis was performed by the laboratory of Sachsenforst public enterprise, following standards of forest soil chemical analysis. Spectral data was obtained from 2018 - 2020 using Veris vis-NIR Spectrophotometer by Veris Technologies (spectral resolution: 6 nm), To capture the samples variability, 10 measures were taken, rotating the samples after every measurement. Then, the mean of the single measures was formed. The data was used to predict humus properties for forest soil mapping and monitoring by vis-NIR spectroscopy. Supplement to: Thomas, F.; Petzold, R.; Landmark, S.; Mollenhauer, H.; Becker, C.; Werban, U. Estimating Forest Soil Properties for Humus Assessment—Is Vis-NIR the Way to Go? Remote Sens. 2022, 14, 1368. https://doi.org/10.3390/rs14061368