EVALUACIÓN DEL POTENCIAL DENDROCRONOLÓGICO DE DOS ARBUSTOS QUE COEXISTEN EN ÁREAS DESÉRTICAS DE MONTAÑA DEL CENTRO-OESTE DE ARGENTINA.

Dendrochronological studies with shrubs from arid ecosystems in South America are of great importance due to the scarcity of ecological information that exists in these environments. This approach allows to evaluate the responses of plant species exposed to climate variability under arid conditions. We developed ring width chronologies and evaluated, for the first time for Argentina, the relationship between radial growth and climatic variables (precipitation, temperature and aridity index) of two shrub species characteristic of arid montane environments, Proustia cuneifolia and Hualania colletioides. The chronology of P. cuneifolia recorded a positive correlation with precipitation (May), temperature (October, July and February), and SPEI (June-October). The chronology of H. colletioides showed negative correlation with the temperature of the months of December and February. The results suggest that variations of the annual ring widths of P. cuneifolia are influenced by regional climate, mainly by aridity, while the growth of H. colletioides could be influenced by factors at the scale of microsite. A more extensive network of chronologies is necessary to explore site-climate variability under conditions of a complex topography such as that found in mountainous areas, suggesting the spatial extension of these records in order to understand in more detail the climatic imprint on the annual growth of these shrubs. [ABSTRACT FROM AUTHOR]