Andreasen, Mie; Van der Veeke, Steven; Limburg, Han; Koomans, Ronald; Looms, Majken Caroline (2025): Radionuclide concentrations obtained from gamma-ray spectrometry for soil moisture estimation from agricultural field measurements in Hesbjerg, Denmark [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.977836

The field site is located on clayey soil in Northern Zealand, Denmark. The data is compiled into one text file and include estimated radionuclide concentrations, cosmic-ray neutron intensities, point-scale soil moisture (both time series and campaigns), as well as precipitation. Gamma radiation was measured using the MS1000 detector (Medusa Radiometrics BV) and post-processed using the GAMMAN software (Medusa Radiometrics BV) to obtain the radionuclide concentrations (K-40, U-238, Th-232, Cs-137). The K-40, U-238, Th-232 concentrations are estimated using the Window analysis post-processing method, while the Full-Spectrum analysis post-processing method was used for Cs-137 concentrations. The concentrations were corrected for the effect of biomass water using the method presented in Baldoncini et al. (2019) assuming 70% water content and a linear correlation of biomass yield to vegetation height. Cosmic-ray neutron intensities were obtained using the CR2000/B system (Hydroinnova LLC, Albuquerque, NM, USA) and were corrected for temporal changes in barometric pressure, incoming cosmic radiation and atmospheric water vapor following standard procedures. The point-scale soil moisture time series were obtained using four multi-depth soil moisture sensors (Onset Computer Corporation). The point-scale soil moisture campaigns consist of an average of 34 measurements obtained using a handheld time domain reflectometry (TDR) sensor (Fieldscout TDR 300 Soil Moisture Meter, Spectrum Technologies, Inc.) equipped with 20 cm long rods. More details of the site characteristics, instrumentation and data processing are provided in the paper. The files contain hourly data for the period from May 23rd, 2023, to October 26th, 2023.