The dependence of the soil water content upon thematric potential is studiedwithin a fractal approach that regards the water retention curve as a sequence ofwell defined fractal regimes. Each of such regimes accounts for a given functional dependence ≡ (), which in turn is characterized by a fractal dimension. The difference between the double fractal (observed into sandy soils) andmultifractal (observed into clay soils) regime is explained by recalling that, for a sandy soil, the transition from saturated to dry conditions is driven by a steep reduction of . To the contrary, for a clay (where the change from the highest water contents to the smallest ones is characterized by a large range of thematric potential), the multifractal behaviour is observed. These results are also confirmed by the analysis of experimental data. In particular, we show that the intermediate regime, generally accounting for the fractal multimodality, is due to the sandy nature of the soil at stake, practically immaterial. Finally, we demonstrate that our model can be also regarded as the straightforward generalization of that of Millán and González-Posada (2005).
A fractal analysis of the water retention curve.
Carmine Fallico;
2018-01-01
Abstract
The dependence of the soil water content upon thematric potential is studiedwithin a fractal approach that regards the water retention curve as a sequence ofwell defined fractal regimes. Each of such regimes accounts for a given functional dependence ≡ (), which in turn is characterized by a fractal dimension. The difference between the double fractal (observed into sandy soils) andmultifractal (observed into clay soils) regime is explained by recalling that, for a sandy soil, the transition from saturated to dry conditions is driven by a steep reduction of . To the contrary, for a clay (where the change from the highest water contents to the smallest ones is characterized by a large range of thematric potential), the multifractal behaviour is observed. These results are also confirmed by the analysis of experimental data. In particular, we show that the intermediate regime, generally accounting for the fractal multimodality, is due to the sandy nature of the soil at stake, practically immaterial. Finally, we demonstrate that our model can be also regarded as the straightforward generalization of that of Millán and González-Posada (2005).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.