Modelación del flujo de agua y nitrato en el suelo de la microcuenca Cuevas en el sur de los Andes ecuatorianos empleando Hydrus 1D

With the purpose of studying an integral dynamics between the soil and water factors in the high Andean ecosystems, this research focused on the modeling of water flow and nitrate transport through the sub surface soil solution of the Cuevas microbasin (4.2 km2), in the south of the Ecuadorian Andes. The Hydrus 1D model was used to model the water content and the transport of nitrate through the soil profile in thirty monitoring points distributed in the microbasin under the coverings of páramo, polylepis forest and cushion. The model has been shown to be capable of achieving acceptable adjustments, considering the PBIAS error index, using inverse modeling in the optimization of pedotransference parameters. The results obtained reveal that the soil under the forest cover would be storing a greater percentage of water, up to 10% more than that reached under the coverings of páramo and cushion; On the other hand, nitrate seems to be consumed more under the cushion coverage. The investigation supposes an important advance in the integral study of watersheds; the findings, methods and limitations found in this work could help in the planning of future research within the axis of hydrological and geochemical modeling.