Organic matter, geochemical and colorimetric properties of potential source material, target sediment and laboratory mixtures for conducting sediment fingerprinting approaches in the Mano Dam Reservoir (Hayama Lake) catchment, Fukushima Prefecture, Japan.

The current dataset was compiled to study sediment fingerprintings practices, i.e tracer selection and contribution modelling. Colorimetric properties analysed with a portable diffuse reflectance spectrophotometer (Konica Minolta CM-700d) and geochemical contents obtained with an energy dispersive X-ray fluorescence spectrometer (ED-XRF Epsilon 4) were analysed in potential source material that may supply sediment to coastal rivers draining the main Fukushima radioactive pollution plume (Japan). Three potential soil source materials (n = 56) were considered: cropland (n = 24), as non-decontaminated soil before the application of local decontamination policies: forest soils (n = 22) and subsurface material originating from channel bank collapse or landslides (n = 10). A sediment core was collected in the Mano Dam lake (Hayama lake) on the 6th June 2021 and was sectionned into 1-cm layers (n = 34). Laboratory mixtures (n = 27) were made to assess different contribution levels from the sources. In addition to colorimetric and geochemical properties, organic matter and stable isotopes were analysed by EA-IRMS for sources and sediments samples. The current dataset comprises three Excel files including the metadata description, the data itself and a file describing the composition of laboratory mixtures prepared to provide a dataset to calibrate/validate un-mixing models implemented to address this research question and analysed in the same conditions and using the same equipment as the source/target material