My Account: Log In | Join | Renew
Search
Author
Title
Vol.
Issue
Year
1st Page

Abstract

 

This article in SSSAJ

  1. Vol. 25 No. 5, p. 329-334
     
    Received: Nov 22, 1960
    Published: Sept, 1961


 View
 Download
 Alerts
 Permissions
 Share

doi:10.2136/sssaj1961.03615995002500050008x

Calibration and Characteristics of Two Neutron Moisture Probes1

  1. C. H. M. van Bavel,
  2. D. R. Nielsen and
  3. J. M. Davidson2

Abstract

Abstract

The effect of the size of cylindrical containers filled with soil on the calibration of two types of neutron probes was investigated for moisture contents up to 0.25 volume fraction. Neutron count rates were appreciably affected by the value of both diameter and height up to 3 feet. Differences between 3 and 4 feet were samll.

The response of the end-source probe was linear within the range investigated (0 to 0.40 volume fraction). The data also show that the end-source probe design as compared with the centered-source design is more efficient and, therefore, requires a smaller radioactive source for equal precision.

Once an accurate calibration with soil is available, verifying calibration of probes may be done with NaCl or H3BO3 solutions, limited to probes of identical design but differing efficiencies or source strengths. Relations found between soil moisture content and solution concentration are given.

A discussion of the range of measurement of soil moisture content with neutron probes is presented, comparing various literature data.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © . Soil Science Society of America