The soils, some those considered homogenous, show some spatial and temporal variability of its physical, chemical and biological atributes. To define this variability is very important to efficient soil management. This study had the objective of investigating the spatial variability of some physical attributes of an Red Latosol in Mossoró, state of Rio Grande do Norte, Brazil, to determine the best procedure for soil sampling. Soil samples were collected on a 100 x 100 m area, in 10 m grid marking, from the 0-0.2 m soil layer, totaling 100 samples. The following soil attributes were analyzed: particle size, bulk density, particle density, total porosity, and water retention at tensions of 0.033 and 1,500 MPa. The data were analyzed through descriptive statistics and geostatistics. Results indicated that soil variability, measured by the coefficient of variation, was low for sand, bulk density, particle density and total porosity and intermediary for silt, clay, field capacity, and permanent wilting point. The distribution frequency for most analyzed variables was normal, with exception of sand, bulk density and total porosity. The mapping of the studied variables suggested that the establishment of homogeneous subareas would make the natural resources management, especially of water, more effective.
soil physics; geostatistics; kriging; precision agriculture
