Variabilidade dos limites do intervalo hidríco ótimo

Abstract

The search for indicators of agricultural soil physical quality has been incessant. In this context the least limiting water range (LLWR) which considers as least limiting plant growth condition in addition to the field capacity and permanent wilting point the soil penetration resistance and aeration porosity. The difficulty of establishing relations between LLWR and plant productivity has called into question the validity of this indicator. One reason may be the spatial variability and the weakness of the mathematical models adjustments to variables. The aim of this work was to evaluate the spatial variability and the mathematical models adjustments of each variable. Results indicate high variability of LLWR components, specially field capacity and the weak adjustment of soil penetration resistance. This variable led to data dispersion of LLWR components in the same bulk density