Using a Cosmic-Ray Neutron Sensor (CRNS) to Monitor Vegetation

It is believed that the cosmic-ray neutron sensor can be used to measure vegetation. We compare biomass water equivalent (BWE) to neutron counts from a cosmic-ray neutron sensor. We believe that the thermal neutrons will have a highly correlated inverse relationship with BWE. This is due to the ambient energy of thermal neutrons and the ability of hydrogen to capture them easily. Our results for soybean in 2017 showed that there was better correlation between raw fast neutron count $(\mathbf{R}^{2}= \mathbf{0.61})$ and BWE than raw thermal neutron count $(\mathbf{R}^{2}= \mathbf{0.21})$ . It would be ideal to explore this relationship of fast neutrons to BWE, with the addition of other hydrogen pools at the surface.