Knowledge of soil water at a range of spatial scales would further our understanding
of the dynamic variable and its influence on numerous hydrological applications. Cosmic ray
neutron technology currently consists of the Cosmic Ray Neutron Sensor (CRNS) and the Cosmic
Ray Neutron Rover (CRNR). The CRNR is an innovative tool to map surface soil water across the
land surface. This research assessed the calibration and validation of the CRNR at two survey sites
(hygrophilous grassland and pine forest) within the Vasi area with an area of 72 and 56 ha, respectively.
The assessment of the calibrations showed that consistent calibration values (N0) were obtained
for both survey sites. The hygrophilous grassland site had an average N0 value of 133.441 counts
per minute (cpm) and an average error of 2.034 cpm. The pine site had an average N0 value of
132.668 cpm and an average error of 0.375 cpm between surveys. The validation of CRNR soil water
estimates with interpolated hydro-sense soil water estimates showed that the CRNR can provide
spatial estimates of soil water across the landscape. The hydro-sense and CRNR soil water estimates
had a R2 of 0.439 at the hygrophilous grassland site and 0.793 at the pine site.
Supplementary material: Excel document containing the Cosmic Ray Neutron Rover (raw) data and the Hydro-sense soil water data for
Surveys one, two, three and four, at the hygrophilous grassland and pine forest site.