Soil Hydrology Overview

This data reflects both the quality of the soil structure, the amount of water available for growth and the ease by which these soils are able to be irrigated. The data indicates how much water is available for vigorous tree and fruit growth, as well as how much water is available for tree maintenance and survival. This data can also be used to better schedule irrigation, and compare irrigation requirements between soils.

The topsoil (A1 horizon) is moderately compact having a bulk density of 1.43 g/cm³, a moderate to low saturated hydraulic conductivity for a ferrosol of 92 mm/hr. The drainable porosity at 11.2 % is above the ideal level of 10 % which suggests good macroporosity. These analyses indicate that despite showing signs of compaction the topsoil is still well structured. The A1 horizon contains 19.1 % or 22.9 mm plant available water (PAWC), of which 7.6 % or 9.1 mm is readily available to support rapid growth (Green in Figure 3), 13.8 mm is available to the tree but at a cost to growth (Orange in Figure 3), whilst 18.6 mm is not able for use by trees (Red in figure 2). The B2 horizon appears to be better structured than the A1 horizon. The B2 horizon has lower bulk density 1.25 g/cm³ compared to 1.43 g/cm³ and higher drainable porosity at 13.9 % compared to 11.2 % in the A1 horizon. This provides further evidence that the A1 horizon has a moderate degree of compaction and structure loss. Soil colour and the moderate drainable porosity in the B1 and B2 indicates the soil profile is well drained providing an ideal environment for root growth throughout the soil.