Retention curve on avaluation of soil physical quality

Abstract

Soil is one of the most important natural resources of our planet, causing concern regarding its conservation. Soil quality can be defined as the capacity of each soil to perform its function in an ecosystem, within limits based on its behavior in an ideal system. This quality can be evaluated by measuring some soil attributes or properties. The physical quality affects chemical and biological qualities. Soil structure is a physical attribute that expresses well the soil quality, because it depends on the size, shape and arrangement of the solid particles and pores. Discussing pore arrangement, mechanisms of movement and soil water retention become relevant, through which one can infer many indices of soil physical quality, like the soil water retention curve. Since there is no theoretical mathematical expression for the retention curve, mathematical and empirical models have been used. Another relevant factor is the scope of Oxisols, which is a very important soil class due to its productive potential, being highly weathered soils with high aggregate stability, resulting from the action of oxides present in the clay fraction, grain structure and high macroporosity. Therefore, it is necessary to develop methodologies to verify the physical quality of these soils for the establishment of management systems that aim to agricultural sustainability. For this reason, the project aims to evaluate the soil physical quality by using the soil water retention curve analysis for different adjustment models in Oxisols with three textural classes.