Diagnóstico de la dinámica hidrometeorológica por medio del balance hídrico en la cuenca del Río Topo de la Provincia de Tungurahua-Ecuador

Abstract

This study analyzes the hydrometeorological dynamics of the Topo River basin in Tungurahua through the water balance, a key tool for understanding the hydrological cycle and water storage. The basin, located between páramo and Amazonian regions (1291–4809 masl), features a mountainous landscape with humid forests and steep páramo slopes, characterized by an efficient drainage system and high runoff levels. A hydrometeorological characterization was conducted using data from a station in the lower part of the basin, operated by ECUAGESA, covering the period from January 2021 to August 2022. During this time, annual precipitation reached 4658.63 mm, the average temperature was 17.37 °C, and the average flow rate was 60.88 m³/s. Using Lvovitch’s formula (1959), the water balance revealed a water storage of 50.97 mm, a surplus of 288.28 mm, and a runoff of 6981.93 mm (88.37% of the total precipitation), while actual evapotranspiration accounted for 867.95 mm (10.99%). Additionally, morphometric and hydrometeorological data by sub-basin were evaluated using the SWAT model, yielding results of NSE=0.52, PBIAS=-29, and R²=0.68, indicating moderate performance. It is concluded that the main water storages are located in the upper regions of the basin, due to the presence of lakes and aquifers, although the lower areas, with dense vegetation, also contribute significantly.