Spatial Variability of soil pH and Salinity Under Date Palm Cultivation

Geostatistics provides a set of statistical tools for incorporating the spatial and temporal coordinates of observations in data processing, allowing for description and modeling of spatial patterns, prediction at unsampled locations, and assessment of the uncertainty attached to these predictions. The soil properties vary continuously along the field and cannot be measured everywhere. Thus, the understanding of spatial variability of soil properties will allow better management of soil and crop in the field. The present study aims to investigate the spatial variability of soil pH and EC under date palm at the Agricultural Research and Experimental Station, College of Agriculture, King Saud University located at Dirab and to delineate these properties and their variability in such area using the Kriging technique. The present results clearly indicated that EC and pH soil parameters spatially distributed under field conditions. The spherical model was the best variogram model to fit the present data. The Kriged values had lower variance than measured. The variance ratio of EC parameter was higher than pH parameter. The results indicated that 99.96% of EC variations were due to structural variance or spatial variability of the EC parameter and the random variance was account 0.04% only, while the structural variability of pH parameter was 99.99% and 0.01% only was due to random component (measurement error). It could be concluded that Kriging is the most appropriate technique for delineating the distribution of EC and pH soil parameters. Kriged maps can facilitate the better soil management. Preparation of such kinds of maps before setting up experiments, especially of a long –range nature, such as Date Palm trees, could be helpful in devising ways and means for making valid treatment comparisons. The Kriging can explain about 66.15 and 82.03% of the spatial variability in EC and pH, respectively