The Experimental Station of Aula Dei EEAD-CSIC has become a pioneer worldwide in the use of a portable cosmic ray neutron sensor to measure soil moisture in agricultural systems. The goal is to evaluate how the water content affects the processes of soil degradation due to water erosion, for example (torrential rains), and loss of soil. In addition, it offers information to make estimates about the water needs of crops or any plant cover.
Researchers from the EEAD-CSIC, Leticia Gaspar and Ana Navas, are leading this international project of the joint division of the Food and Agriculture Organization (FAO) with the International Atomic Energy Agency (IAEA), both belonging to the United Nations (UN).
The researchers have carried out field campaigns with the portable Cosmic-Ray Neutron Sensor (CRNS), in different crops, and in cereal fields, fruit trees, pine forests, pastures and other vegetable coverings of Cinco Villas, la Ribagorza, and in the EEAD farm in Montañana.
They have carried out sampling work in order to track how soil moisture varies in different seasons, fields, and crops.
The information generated is being processed in collaboration with Professor Trenton Franz of the University of Nebraska (USA) and the Soil Laboratory of FAO-IAEA in Seibersdorf (Austria).
The exhaustive characterization of soils available to researchers of the EEAD and its "Erosion and Evaluation of Soil and Water" group will allow calibrating the CRNS sensors for use in similar latitudes and soils around the world and thus help optimize irrigation water, the study of runoff models (one of the main causes of erosion worldwide), and soil loss.
The CRNS provides a reliable estimate of soil moisture by counting the levels of neutrons in the air from cosmic rays that enter the atmosphere and reach the surface of the soil.
The level of neutrons is controlled by the number of hydrogen atoms in the soil-air system that are directly related to the water content in the soil. CRNS allows generating spatially distributed data of interest to know the soil moisture status, which allows researchers to evaluate how the water content affects the runoff and soil loss processes.
It is a very powerful tool that allows measuring the real humidity status of the soil to complete and contrast field measurements with the data provided by remote sensors, such as satellites.