Nuclear Techniques for Soil Moisture Measurement Used to Improve Irrigation Management: An Overview

Adopting novel policies in the agricultural sector as the largest consumer of water should undeniably lead to increased water use efficiency and reduced water loss. New technologies including nuclear techniques can be of great help in improving irrigation management through optimized water use efficiency. Study has shown that instrumental monitoring of soil moisture and biomass can be exploited to determine the required irrigation timing and volume. In this regard, such nuclear tools as neutron meter and cosmic ray neutron sensor (CRNS) as novel technologies, installed on farms either in spot installations or in networks, are capable of estimating soil moisture through detecting hydrogen within soil H2O molecules and decelerated neutrons. It has been confirmed that these technologies are beneficially effective in scheduling irrigation by predicting the incidence of imminent moisture stress and, thereby, determining proper irrigation timing, which will evidently enhance both water use efficiency and crop yield. This article provides an overview of the development and application of nuclear and isotopic techniques (NITs) in irrigation management and introduces methods of NITs tool calibration.