An Estimation of Corn yield losses arising from water shortage by measuring thermalized neutrons

Abstract

Droughts are one of the most significant factors disrupting crop growth and development. This study applied a nuclear technique based on thermalized neutrons to estimate maize yield losses arising from water shortages. The biomass consists of water and light hydrogen (1H), which slows down fast neutrons. Hence, thermalized neutrons can be a helpful proxy to determine crop losses. An experiment was conducted with four treatments related to various levels of water stress in three replications. At the end of the maize growing season,, wet weight of the samples was measured, and then the samples were put around an access tube of the Hydro-probe Neutron Meter to count thermalized neutrons. Thereafter, the samples were then transferred to the oven to measure dry weight and in turn, biomass water equivalent (BWE). Findings showed that the average values of the thermalized neutron count ratio were positively and negatively correlated with BWE and damage (%), respectively. The regression models estimating crop losses were cross-validated based on the leave-one-out technique. An absolute mean error equal to 15% and R 2 greater than 0.6 indicate somewhat satisfactory performance of the models. This study was a breakthrough in the feasibility of applying these instruments. Further studies are recommended for practical applications.