Balance hidrológico de un pedón de suelo en el ecosistema del páramo en el norte del Ecuador.

Abstract

In the present titling project, a hydrological balance of a 1m2 cross-section and 1m deep soil sample, which integrates five horizons of different thicknesses differentiated by their physical characteristics, was carried out at the coordinates: 0.47° S, 78.21° W at an elevation of 4250 m.a.s.l. within the Antisana Water Conservation Area (ACHA). The objective was to estimate surface and subsurface flows on a daily scale from November 2020 to September 2021, taking soil moisture as a state variable. The equation used for the hydrological balance was dθ/dt=1/L(T-R-q-S) for the surface horizon and dθn/dt=1/L(q(n-1)-S-qn) for the subsurface horizons, where: throughfall (T); runoff (R); percolation (q); root water uptake (S); moisture variation per day (dθ/dt); horizon number (n). Pedon instrumentation was performed as part of the Eddy Covariance tower system funded by the PIMI-17-04 project. The daily results of the state variable showed a dynamic of values in which the average in horizons 1 to 5 was 30.33, 21.98, 12.25, 10.73 and 10.03 %, respectively, denoting that moisture decreases the deeper the horizon is. The performance metrics used were: Mean Absolute Error (MAE), Root Mean Square Error (RMSE) and correlation coefficient (CC), where acceptable performance values were obtained. It was concluded that the hydrological model proposed allows understanding the partitioning of surface and subsurface water of the different horizons of the soil pedon.