Estimation of the Water Balance of a Small Tropical Andean Catchment

Abstract

The present study seeks to estimate the water balance that results as a product of the variation of precipitation and temperature over the Chaquilcay microcatchment, a natural system that intercepts with the surface of the Aguarongo Protected Forest in Gualaceo, Ecuador. Four meteorological stations of the National Institute of Meteorology and Hydrology (INAMHI) were studied, which are divided into climatological and pluviometric, with time series of over 30 years, (1982-2015 period). In order to quantify the contributions and losses of water, statistical analyzes of the time series and surveys of in situ information were carried out. The methods used are linear regression, streak test and double mass curve. To fill and validate the series of precipitation and temperature, reference temperatures of the isothermal raster of Ecuador were included in the pluviometric stations. Additionally, a digital elevation model (MDE) was used to predict the amount of sunshine, and the Thornthwaite evapotranspiration method (1948) was applied from the obtained data. The results show acceptance of the meteorological records, while in the soil analysis we obtained the following data: Humidity, 62.38%; organic matter, 21.29%; field capacity, 18.71 mm and a flow of 1.89 m³ / s during the month of May. Finally, the water balance indicates 843.7 mm of annual precipitation, a storage difference of 18.71 mm representing 2.22% of total precipitation, an surplus of 144.5 mm, and actual evapotranspiration of 680.5 mm, with 17.13% and 80.65%, respectively.

Soil Fungal Diversity of the Aguarongo Andean Forest (Ecuador)

“…The Aguarongo forest reserve is one of the most important biodiversity hotspots in Ecuador, and in recent years, it has been the subject of numerous research studies on flora, fauna, use of soils, and water balance [ 28 , 42 ].…”

“…The Aguarongo forest is one of the few fragments of Andean forest remaining in the Andean mountains in the province of Azuay and corresponds to low montane humid forest. The area, with an extension of 2080 ha, is the main water supply for the communities of the Gualaceo, Sigsig, and Cuenca cantons in southern Ecuador, resulting from its 191 streams [ 27 , 28 ]. It is located in the southern part of the middle basin of the Paute River, between 78°48′54″ and 78°52′22″ W, and 2°52′37″ and 2°59′43″ S. The altitude ranges between 2900 and 3320 m.a.s.l., and the average annual rainfall is 820 mm.…”

Caracterización hidrológica de la microcuenca del estero Hondo, cantón La Maná, Ecuador

“…Estos datos se asemejan con lo obtenido por Duque et al (2019) donde menciona que, dentro de su estudio sobre la estimación del balance hídrico de una cuenca andina tropical, la precipitación anual en la microcuenca del río Chaquilcayen ubicada en el cantón Gualaceo fue de 843.4 milímetros; esta precipitación disminuye hacia la parte del este de la cuenca.…”