Uso da aproximação fractal para ajuste da curva de retenção de água no solo.

Abstract

Currently the fractals geometry have been used as an alternative tool for elaboration of mathematics models in the estimate of the water retention curve in the soil. Utilizing the fractal geometry concepts, BROOKS e COREY (1964) and PERRIER et al., (1996) propose a model, which it esteems the soil humidity in function of the soil water tension data. The objective of this work was to estimate the retention curve using the Brooks e Corey (1964) model, modified utilizing the fractal geometry, with a new parameter of interpolation called fractal dimension (D), and it seeing that depends of the soils proprieties. The D parameter that represents the fractal dimension of the Brooks e Correy model was determined based on two physical proprieties; the soil water content, DSWRC, and of the distribution of size of the soil particle, DPSD. For the application of the proposal model and determination of the fractal dimension were collected 36 samples of deformed soil in three depths 0- 20, 20-40 and 40-60 cm, in an area cultivate with sesamum and irrigated with sprinkles system. The Brooks and Corey model, modified for fractal dimension, it showed results more significant on attainment of the retention curve, when it was compared with the use of the fractal dimension DPSD. However, in both cases there are a series of additional conditions that it allows the attempt of obtaining of several results.