Efectos de los controladores hidrometeorológicos en la concentración del carbono orgánico disuelto (COD) en el agua de suelo y río de una cuenca de páramo andino

Abstract

The Páramo ecosystem has high importance for High-Andean communities, because its capacity of storage water, capacity attributed in part to the high content of carbon in the soils. This property could be altered by changes in the soils characteristics, hydrometeorology and landscape variables. Despite the above, there is low information about the carbon dynamics in this ecosystem. For this reason, in this study we analyze the influence of hydrometeorological Dissolved Organic Carbon (DOC) concentration controls on the soil and stream water in an Andean Páramo catchment. For this purpose, a temporal, correlation and discriminant analysis by flow conditions and a dispersion type analysis between the measured hydrometeorological parameters and the concentration of DOC in the soil and flow water was carried out. The study catchment (Zhurucay river catchment) is located in southern Ecuador, 85 km southwest of the city of Cuenca, where the Zhurucay Ecohydrological Observatory has been established. This catchment has an area of 3.28 Km2 with an altitude range between 3656 and 3917 m a.s.l. and a relatively uniform precipitation distribution throughout the year with a rainfall volume of around 1200 mm per year. It was observed that the DOC concentration had a variation related to the precipitation for stream water, while in soil water no variability linked to precipitation was observed. However, when the effect of the hydrometeorological variables was analyzed, it was found that precipitation, evapotranspiration and streamflow were the variables with the greatest influence on DOC dynamics for all the studied compartments. In conclusion, the greatest controller of DOC concentration in the Páramo ecosystem is precipitation, which is closely related to streamflow. Both variables can be significantly influenced by climate change and land use changes, so the COD concentration can be an initial indicator of these changes.