Patrones de distribución de raíces finas en plantaciones forestales de Eucalyptus pellita F. Muell., sometidos a distintos esquemas de fertilización con potasio, calcio y fósforo en Puerto López (Meta).

Abstract

In Eucalyptus pellita F. Muell plantation, fertilized with different doses of Cal dolomite (t / ha), Triple Superphosphate - SFT (Kg / ha) and Potassium Chloride - KCl (Kg / ha), located in the Colombian Orinoquía, zone of tropical climate, with a precipitation of monomodal regime, soils with very low potential fertility and high acidity. Cores, were installed, for evaluation of internal growth of superficial fine roots in 4 defined distances from the tree, in randomized complete block design 3x3x3 in the series modality of experiments at different sites and at the same time; with the purpose of knowing the incidence of fertilization in the distribution of roots. Samples were collected every three months for a year. Diameter (mm), length (m) and root surface area (cm2) were determined using the Winrizho software, these variables were analyzed together with physical properties of the soil. The action of the three fertilizers is essential to stimulate the development of fine roots, third degree interaction occurs, indicating the mutual dependence of the sampling site with the application of Cal, SFT and KCl. The length and surface, with respect to the effect of the locations from the tree was significant for the nearest cores (37.5 cm). The treatments with greater root development are found in areas of low and medium penetration resistance between 12.18 - 12.68 kPa and low tangential resistance to cutting between 54.4 - 55.6 kPa. The dose and form of application of fertilizers affect the distribution of the roots, however, they fail to overcome the physical limitations imposed by the soil. Greater root concentration is confirmed with high doses of SFT and the tendency of species that grow in soil with thick textures to have more lateral roots that seek to explore larger volumes of soil.