IANIGLA   20881
INSTITUTO ARGENTINO DE NIVOLOGIA, GLACIOLOGIA Y CIENCIAS AMBIENTALES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Austrocedrus chilensis response to mean and extreme climatic variability along a precipitation gradient in northern Patagonia, Argentina.
Autor/es:
AMOROSO, MARIANO; MARCOTTI, EUGENIA; VILLALBA, RICARDO; MUNDO, IGNACIO
Reunión:
Congreso; 9th International Conference on Dendrochronology; 2014
Resumen:
The  steep  west-to-east  precipitation  gradient  in  the  rain  shadow  of  the  Andes  drives  dramatic  changes  in vegetation  patterns.  As  a  result  of  this  abrupt  gradient,  Austrocedrus  chilensis  populations  develop  at  sites widely ranging in moisture, receiving as much as 2000 mm in the western limit and as little as 600 mm in the eastern limit of its distribution in the forest-steppe ecotono. This remarkable change occurs in a narrow strip of only 40 kilometers making this precipitation gradient one of the most abrupt in the globe. We conducted a dendroclimatological study to quantify and compare the influence of mean and extreme climatic variability on the radial growth of A. chilensis populations growing across this precipitation gradient. We sampled sites along the  gradient  to  build  tree  ring  chronologies  to  study  climate-growth  relationships.  Correlation  function analyses  were  used  to  study  the  influence  of  macroclimatic  factors  on  tree  growth.  The  effect  of  extreme climatic events (droughts) was studied by comparingtree growth during drought and post-drought years  with the mean growth of the previous decade. Preliminaryanalyses indicate a strong relationship between radial growth and precipitation but this might vary acrossthe gradient. While the growth response to the past major droughts  varied  across  the  gradient  depending  on  the  drought  type  and  the  site  conditions,  stands  at  high precipitation sites appeared to be the most affected. Studies on such dramatic precipitation gradientsare of great importance as these areas will be strongly affected under the future climate scenarios.
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