Thermo–Time Domain Reflectometry Method: Advances in Monitoring In Situ Soil Bulk Density

Abstract

Soil bulk density (ρb) is a critical parameter for describing soil structure and physical processes, yet traditional methods are unable to capture spatial and temporal changes in ρb. Recently the thermo–time domain reflectometry (thermo-TDR) technique has been applied to determine in situ ρb on the basis of soil thermal property and water content measurements. Here, we present theory, instrumentation, procedures, and comments for monitoring in situ ρb with the thermo-TDR sensor. We conclude that the thermo-TDR sensor offers a useful tool for determining ρb continuously and nondestructively.