Analysis of spatial and temporal stability of water storage in the Cambisol Valley region of Açu, RN

Abstract

Irrigated fruit growing in the Açu Valley is an important component of the Potiguar agribusiness. Knowledge of the spatial and temporal behavior of water in the soil is essential for precise irrigation management. This study was conducted aiming to analyze, by means of geostatistics, the spatio-temporal variability of water storage in the soil and the temporal stability of these variations. The studies were conducted in an area cultivated with hoses (Manguifera índica L.), irrigated by micro in Alto do Rodrigues, RN. Monitoring soil water was by tensiometers. In the evaluation of temporal stability, we used the techniques suggested by Vachaud et al. (1985) and Kachanoski and Jong (1988). The results indicated adequate geostatistics to describe the spatial dependence structure, and soil water storage present spatial variability in the area, showing the need to manage irrigation differently and not considering the homogeneous area, as is currently done in practice. The water in the soil showed temporal stability in all sampled points. And, this condition provides the identification points in the area that have values representative of the spatial average.