No significant differences in measured SOC stocks occurred between the three land uses of the Plains region, where variation both within and between land use groups was particularly low on the sampled Xeralf (red brown earth) soil type (Table 3).
In the Plains region, selected land uses were (i) continuous cropping, (ii) rotational cropping, and (iii) pastures on Xeralfs (red-brown earths).
Sampling regions and land use descriptions Two soil types and six land use groups were selected for sampling (Stephens 1953; Soil Survey Staff 1994) Rainfall Soil type Major Description zone land use Plains region 350-500 mm Xeralfs (red- Pasture Sites in pasture at least (average brown 9 years out of the last 431 mm) earths) 10.
The clayey Xeralf soils remained a challenge to the plough because of their stiff dry clay and were better suited to rough pasture for cows and sheep.
Some Xeralfs were converted to olive and citrus orchards, with the ready availability of plastic irrigation piping in the twentieth century.