Characterizing spatial variability of some soil properties in Beni-Moussa irrigated perimeter from Tadla plain (Morocco) using geostatistics and kriging techniques

Abstract

The research was carried out in Beni-Mousssa perimeter in the southern part of the Tadla plain, in Morocco. This study was performed using physicochemical analyses combined with statistical and geostatistical analysis to understand the spatial variability of soil quality in this agricultural area and to elaborate sustainable management of soil and environmental decision. The locations of sampling sites were defined by knowledge of the region’s farmers, on-site observations, and analyzed in the laboratory using the standard procedures for each soil property. A total of 67 soil samples were collected and analyzed in Geo-Resources and Environment Laboratories at the Faculty of Sciences and Techniques of Beni-Mellal, to identify physical and chemical soil properties especially pH, electrical conductivity (EC), organic carbon (OC), carbonate content (CaCO3), texture, exchangeable potassium (K), total phosphorus (P), total nitrogen (N), and cation exchange capacity (CEC). The soil presented an alkaline reaction. Other soil characteristics varied considerably in the overall study area. Pearson correlation among pH, soil OC, and CaCO3 were considered to be positive and significant (p < 0.05). Gaussian, exponential, spherical, and K-Bessel semivariogram models were selected, with weak to strong spatial dependency to be the better adjustment by using ordinary kriging techniques to estimate the spatial variability of soil characteristics. The obtained results revealed that the variation of soil characteristics in the study area depended on intrinsic and management soil factors. The detailed maps obtained in the framework of this type of study are very useful at international level in the selection of appropriate interventions, in particular with regard to the quantity of fertilizers, crop rotation, conservation and rehabilitation of deteriorated soils.