Soil water storage is very variable in time and space due to the influence of various environmental factors and topography. The objective was to: i) quantify the soil water storage, ii) assess the temporal stability and spatial variability of a point near to and one distant from the root system in a common bean - black oat succession iii) verify the spatial variability as a function of the soil relief. In the experimental area (1500 m²), in Piracicaba-SP (latitude 22° 42'30 "S, longitude 47° 38'00" W; 546 m asl) 60 sampling points 5 m apart from each other were established in a 6 x 10 grid (50 m x 30 m). Water storage of the studied soil had a standard behavior pattern, with greater values in the deeper than in the surface layer. A greater temporal stability of soil water storage was observed during the rainy season, but temporal stability was also observed during soil drying, but with higher correlation coefficients in the 0.0-0.80 m layer, showing that this stability was clearly due to the topographical position of these points, in the lower part of the landscape. Point 52 was chosen as representative of the average in the phase of soil water recharge in both layers studied and point 46 as average in the surface layer during the soil drying phase. The spatial dependence of the variability of soil water storage was detected in both soil layers, but with a greater range in the 0.0 - 0.40 m layer in the case of rainfall. When the rains stopped, the range was higher in the 0.0-0.80 m layer. During the rainy season, the pattern of spatial variability was very similar in both soil layers; water storage was highest at the points of highest slope and of depressions in the ground.
relief; soil moisture; relative difference
