Juan Sebastian Martinez Olaya
Ingenio Risaralda S.A., Colombia; jsmartinez@ingeniorisaralda.com
In the Cauca River Valley, about 117,000 ha are affected by excess magnesium in the soil. Traditional management has followed a principle similar to sodium management: increase calcium levels. To study calcium dynamics in soils with high magnesium saturation dedicated to sugarcane production located in the northern part of Cauca Valley, three experiments were established at the Ingenio Risaralda, two of them in the field (plant cane and ratoon) under a randomized complete block experimental design (RCBD), and one under controlled conditions (containers) in a completely randomized design (CRD). Seven treatments were applied in five replications for 35 experimental units. The effect of two amendments (gypsum and calcium carbonate) and three doses corresponding to 1.5; 3; and 4.5 t ha-1 were evaluated. Growth variables, cane yield (TCH), sucrose accumulation (%), sugar yield (TSH), dry matter (g), nutrient content in soil and leaf tissue, and physical parameters associated with soil structure (bulk density and porosity) were measured. The results show increased growth and productivity with the application of calcium carbonate; however, gypsum did not show significant differences relative to the control. The application of amendments favoured the accumulation of calcium and sulfur in the soil and the tissue. The physical properties associated with the structure improved substantially with the application of gypsum and to a lesser degree with calcium carbonate.