Variabilidad espacial de la resistencia a la penetración en un haplustert crómico bajo pasto natural

Abstract

Soil resistance to penetration is a way to determine soil compaction and it is important to determine its spatial variability to be able to properly manage this resource. The work was carried out with the objective of evaluating the spatial variability of the resistance to penetration in a Chromic Haplustert under natural grass. An area of 1.08 ha was chosen, with extensive seasonal grazing of low intensity, belonging to the Provincial Research Station of Sugarcane of Holguín. It was divided into 8 rectangles of 30x45 m (0.135 ha). By simple random sampling, one was chosen, in which 70 points with 5 m distance were sampled. For the determination of the soil resistance to penetration, an IAA/Planalsucar-Stolf impact penetrometer was used. The evaluation was performed at depths of 0-10, 10-20 and 20-30 cm. The highest soil resistance to penetration was found in the 10-20 cm layer. The experimental semivariograms were adjusted with spherical and exponential models, with an independent semivariance of the similar sampling distance in the three depths, in which the penetration resistance values show a strong to moderate spatial dependence. The soil resistance to penetration showed the lowest spatial variability in the depth of 20-30 cm. The lowest soil resistance to penetration was found where the points coincided with a saline plaque. The highest soil resistance to penetration was observed at the edges of the saline bald, from where a compacted soil tongue separates this area with sites of high soil resistance to penetration.