Modeling of the change of physical properties on the water performance of a Ferralitic soil

Abstract

The main objective of this work is to model the effect of the change of the physical properties and hydric behavior in a clay soil and the available water for plants using a simulation tool validated for these conditions. The soil and climate reference data were generated in previous studies in the Experimental Station of the Institute of Agricultural Engineering (IAgric), located in Alquízar, in Artemisa province, where soil is classified as Red Ferralitic and the climatic characterization used was from 1985 to 2010. It was used the MACRO model that constitute a mechanistic model of water and solute transport previously validated for this soil and climatic conditions. It was used the model option for estimate hydraulic properties of the soil using pedotransfer functions to estimate variations in these properties starting from variations in bulk density in upper soil layers (0-40 cm). The results show the decrease of bulk density in 0,1 g.cm-3 in studied soil layers may produce an increase in water retention capacity until 15% and can produce a decrease in water needs between 30 to 20% for dry period and between 90 to 35 % in wet period, increasing soil infiltration capacity about 30% with a more slow redistribution process.