A trial electrical image line was first measured crossing plots 6, 5, 4 and extending to plots 16 and 17 (Fig.
Neutron soil moisture measurements were usually carried out the same day or the day after the electrical image measurements.
Both NMM and electrical image data were not corrected for soil surface height change resulting from changes in soil water content.
The electrical image is constructed by varying the location of the 4 electrodes along the line of interest and by changing the spacing between the electrodes to change the depth of penetration.
A preliminary 245-m-long electrical image line was measured using an electrode spacing of 5 m to determine whether sensible bulk resistivity anomalies were associated with resident plant populations and plot fallowing histories.
7736, n = 228) between the neutron soil moisture count data and the bulk EC derived from inversion of the electrical image data.
11, which shows an electrical image measured alongside the track beneath Dicks Creek Road and the quarry lake (location shown in Fig.
There is a close correlation between the bulk EC indicated by the electrical image results and the fluid EC determined by sampling.
Acworth RI (1999) Investigation of dryland salinity using the electrical image method.
Electrical images (Acworth 1999) were measured along the line of the tree break 3 times (1990, 1996, 1999) to investigate possible changes in bulk electrical conductivity with time.
The sharp lateral variation in bulk electrical conductivity within a single field at Yarramanbah, discovered using the electrical image
method, indicates that a broad-scale process such as evapotranspiration cannot be responsible for the electrical conductivity distribution at this site.
While these observations were mostly derived from measurements performed in the hole at meter-scale, centimeter-scale electrical images
have recently been recorded throughout the hole and are still being analyzed.