While many studies have mapped the thickness of individual soils horizons, few have mapped the horizons as a whole soil profile. We developed soil-landscape regression models to describe and predict the occurrence and the thickness of several soil horizons to 1 m depth. The study was carried out at a 75 km2 area in the Hunter Valley, New South Wales in Australia, using 1050 soil profiles observations. The landscape factors that were used to make the models included terrain attributes, landuse, and geology. We derived regression models to predict the thickness of the individual soil horizons. Because not all horizons can be present in the whole area, we cannot develop a regression model which has the assumption of constant error variance. Therefore, we used a combination of a logistic regression with an ordinary regression to first model the occurrence of each horizon and then their thickness, respectively. This model revealed significant relations between the soil attributes and the prediction of the occurrence and thickness of each of the soil horizons.
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