Abstract

(Introduction):  Highland Andean wetlands are key for maintaining the ecosystem service of water regulation, essential in the fluvial dynamics of watersheds.

(Objective):  To evaluate the influence of climate variability in tropical highland headwater swamps of Miguaguó watershed in Venezuela.

(Methodology):  For this, a time series of 46 years was defined, which was climatologically typified from the Oceanic Niño Index (ONI). 15 climatologically different sample years with availability of LANDSAT images were chosen, to evaluate the spectral behavior of the vegetation in the swamps through the Moisture Stress Index (MSI). The MSI values were statistically compared with the ONI and with local climatic indicators, and the percentage deviations of the anomalies with respect to a standard year were estimated.

(Results):  The results showed that the hydrological dynamics of wetlands is influenced by the combination of ENSO (El Niño / La Niña) anomalies and neutral years, although the impact seems to be differential, depending on the location of the swamps in the landscape, the local biophysical conditions, the interannual sequential relation and intensity of the anomalies. On the other hand, the dominant trend of deviation was the water recovery occurring during Niña events as well as in neutral years, being wetlands more sensitive to La Niña anomalies and showing hydrological resilience.

(Conclusions):  Although the results were clear and conclusive, they have a limited spatial and temporal scope, being the processes studied extremely complex; hence, additional research is required to complement the objective understanding of the climatic and atmospheric relationships of the hydrological processes in tropical highlands.

Keywords: Andean swamps; climatic anomaly; ENSO; headwater catchment; Moisture Stress Index (MSI)