Simultaneous determination of soil bulk density and water content: a heat pulse‐based method

Abstract

Soil bulk density (ρb) and volumetric water content (θ) determine the volume fractions of soil solids, water and air, and influence mass and energy transfer in soil. It is desirable to monitor ρb and θ concurrently and non‐destructively. We present a heat pulse‐based method for simultaneous determination of ρb and θ from soil thermal properties. The method uses equations that relate ρb and θ to soil volumetric heat capacity (C) and to soil thermal conductivity (λ). We developed a three‐step procedure to calculate ρb and θ from C and λ measured by a heat pulse sensor, with soil texture and specific heat of soil solids known a priori. Laboratory evaluation of soil samples with various textures showed that the three‐step method provided reliable estimates of ρb and θ at θ values greater than the critical water content (θc) when λ started to respond notably to increases in θ. This method provides a new way to determine ρb and θ simultaneously with heat pulse sensors.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jul 12, 2018
Source ID
10.1111/ejss.12690

Entities

People

  • R. Horton
  • Tusheng Ren
  • Yili Lu

Organizations

  • China Postdoctoral Science Foundation
  • Iowa State University
  • National Natural Science Foundation of China

Tags

Readers

  • Computer Science/Computer Engineering/Data Science/Digital Signal Processing.
  • Fluid Dynamics.
  • Pavement Materials Engineering.