Intervalo hídrico optimo en suelos alfisol, inceptisol y entisol con cultivo de banano en los cantones Santa Rosa y Machala

Abstract

Within the banana sector, the drop in production related to soil problems has become one of the main factors that has not yet had much intervention to improve its quality. The study of the optimal water interval is one of the new and efficient alternatives as an indicator in response to soil quality in which the concept of useful water is included between field capacity and permanent wilting point. The IHO has been reflected as a variable that indicates the influence of soil water with the crops, due to which the interval is the water range by which the growth of the plants is not limited by the water potential (-0.03Mpa at -1.5 Mpa), by aeration (> 10% of macropores) or by resistance to penetration (<2Mpa). For this, it was established as objectives to estimate the IHO of three types of soil in banana crops using the physical properties, in Inceptisols, Alfisols and Entisols and to relate the IHO using water retention and soil resistance. Samples were collected in the Machala and Santa Rosa cantons of the province of El Oro, whose samples were submitted to the Laboratory of Physics and Soil Chemistry Analysis of the University of Cuenca, for the determination of the water content at 33, 100, 500 and 1500 KPa, a pressure cooker and ceramic plates were used. The statistical analysis was performed using a multivariate Anova with a Tukey test at 90% reliability (p <0.10). To determine the moisture content at 1500 KPa, disturbed sample was used, sieved by 2 mm. Once the equilibrium was reached, the samples were weighed and 3 penetration resistance readings with digital penetrometer were recorded for each cylinder. Then, the samples were dried in an oven at 105 ºC until constant weight in order to determine the water content and the apparent density at each matric potential of the water retention curve. The average values of the IHO in Alfisoles soils in the upper stratum of 1.1 g.cm-3 is high with 0.321 cm-3cm-3, while the apparent density increases, the water interval decreases to the stratum of 1.5 g.cm-3 with 0.086 cm-3cm-3, whereas in Inceptisols the density of 1.1 can be observed an optimal range of 0.243 cm-3cm-3 and that decreases until reaching the density 1.3 g.cm-3 with 0.111 cm3cm3, therefore , its critical limit is given in the density of 1.4 g.cm3 where the IHO value tends to 0, whereas in Entisoles soils it has a greater range in the densities of 1.1 to 1.2 g.cm-3 with a volume of 0.124 a 0.121 cm-3.cm-3, this value decreases in the strata from 1.3 to 1.4 2 g.cm-3 with values of 0.099 to 0.087 cm-3.cm-3 and that tends to 0 in the density 1.5 g.cm -3.As a conclusion of established that in Alfisoles and Inceptisols soils, its critical limit is 1.5 g.cm-3.