Diagnóstico da qualidade do solo em um pomar de citros cultivado com plantas de cobertura nas condições ambientais do Recôncavo da Bahia

Abstract

The soil is a dynamic, natural body, with great importance for life in the earth. Basic and essential source for the humanity support, it has environmental and biological functions that provide a medium for plant growth, animal habitat and microorganisms regulate the water flow in the environment and provide nutrients for the plants. The capacity of the soil to function effectively in the performance of these and others functions is called “soil quality”. The aims of this work were diagnostic the soil quality and characterize the soil resistance to root penetration in a citrus orchard cultivated with a green cover of pig beans (Canavalia ensiformes, L.) in the Recôncavo Baiano. It was used the soil quality index model proposed by Karlen & Stott (1994) and to evaluate the soil resistance to root penetration was used the methodology described by Stolf et al. (1983). The results showed that the global soil quality index is bad, indicating serious limitations for citrus production, as well as the use of a green cover of pig beans, contrary to the expected, its use didn’t result in improvements of the soil quality indicators, demonstrated that the time of use, repetitions and the low quantity of vegetables residues weren’t enough to improve the capacity of the soil to vegetable production. The soil resistance to root penetration presented a different distribution, a high variation coefficient and strong negative correlation with the soil water content. The models tested were well adjusted and adequate to describe the relation between the soil water content and soil resistance to root penetration. The exponential model showed the best index for this relation.