Variabilidad espacio-temporal del contenido de materia orgánica en un vertisol plantado con caña de azúcar bajo diferentes sistemas de manejo

In soils cultivated with sugarcane, organic carbon content is strongly influenced by crop residues and increases with the number of ratoons. Our objective in this study was to analyze the spatiotemporal variability of organic matter content in a pelic vertisol soil planted with sugarcane under different management systems in areas of the Provincial Station of Sugarcane Research in Holguín, Cuba. We used a split-plot experimental design with three treatments and four subtreatments. Harvests were collected with a sugarcane harvester in plant cane and four ratoons. The sampling was done before planting the ratoons and after the harvest, managing harvest residues and applying fertilizers in each case. We determined the soil organic matter content, and the exploratory data analysis was performed using the Statistica 7 software. The experimental semivariograms were fitted using the appropriate theoretical models, and the semivariograms and kriging were performed using Surfer 8 software. Soil organic matter content decreased in the plant cane below the values before planting. It reached stability in successive ratoons, increasing its percentage after the fourth ratoon’s harvest without reaching the initial levels. The improvement was more noticeable with crop residue conservation and the use of organic fertilization. Crop residue conservation in the field reinforced by organic fertilization proved to be appropriate for protecting soil from the deterioration of its chemical fertility.