Foreword: This report summarizes the results of laboratory measurements of the infrared reflectance of selected living plants typical of the natural watersheds in northern Utah. Data indicate that the IR reflectance decreases as the moisture content of the soil decreases and the moisture tension in the soil increases. Additional data will be collected in the field to confirm the results and to further tests the feasibility of using IR reflectance of vegetation as an indicator of soil moisture conditions on the watershed. Mr. Briscoe, Research Physicist, has been responsible for the gathering of laboratory data and has written the manuscript for this report. Introduction: The continuing world-wide population explosion is placing an ever-increasing demand on present usable water supplies, and water shortages are becoming more severe. While scientists and engineers are working to produce additional fresh water by weather control or desalination, much can be done to alleviate water shortages by better management of our watershed areas. In order to make optimum use of our watersheds, we must develop improved methods of determining the water conditions within them. An important contribution toward improved watershed management would be made if some method could be devised which would facilitate data aquisition of watershed parameters. The purpose of this study has been to investigate the feasibility of measuring these parameters by remote reconnaissance methods. The remote sensing technique has been applied, to some extent, in the science of hydrology. Although some of the measurements taken have indicated that various hydrological factors influence the data received, comprehensive results are not available relating to quantitative measurements of water conditions. The procedure followed in this study was to conduct a literature survey of data available at all regions of the electromagnetic spectrum, and then to perform laboratory spectral measurements on certain areas which showed promise.
Briscoe, Ralph D. and Haws, Frank W., "Using Remote Infrared Sensors to Detect Changes in Moisture Conditions on Natural Watersheds" (1967). Reports. Paper 582.