Water content in a soil is determined by measuring the attenuation of secondary background cosmic radiation as this radiation propagates through a layer of soil and water. By measuring the attenuation of secondary cosmic radiation in the range of 5 MeV-15 MeV it is possible to obtain a relative measure of the water content in a soil layer above a suitable radiation detector and thus establish when and how much irrigation is needed. The electronic circuitry is designed so that a battery pack can be used to supply power.
STATEMENT OF GOVERNMENT INTEREST
The Government of the United States has rights in this invention pursuant to contract No. DE-ACO4-94AL85000 between the United States Department of Energy and the Sandia Corporation for the operation of the Sandia National Laboratories.