IANIGLA   20881
INSTITUTO ARGENTINO DE NIVOLOGIA, GLACIOLOGIA Y CIENCIAS AMBIENTALES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Small-scale interactions between wind blowdown and avalanches shape Nothofagus forests in southern Patagonia.
Autor/es:
AMOROSO, MARIANO; VILLALBA, RICARDO; RADINS, MARCOS; BLAZINA, ANA PAULA; RUIZ, MATIAS; SRUR, ANA
Reunión:
Congreso; 9th International Conference on Dendrochronology; 2014
Resumen:
Wind  blowdowns  and  avalanches  are  important  disturbances  affecting  the  temperate  mountain  forests  of southern Patagonia. In previous research, we reported for the first time the occurrence of wave regeneration after wind blowdowns in continental Nothofagus pumilio forests. Furthermore, we identified the presence of avalanche channels and debris in several blowdown patches, but it is unknown how these two disturbances may interact. We undertook a retrospective study todate wind blowdown and avalanche events to study the disturbance?s interaction and to reconstruct the overall forest structure and dynamics in Nothofagus pumilio forests in Santa Cruz, Argentina. We used (i) vegetation transects along the regenerating patches and adjacent undisturbed  forests  to  reconstruct  wind  blowdown  events,  (ii)  standard  avalanche  reconstruction methodology to date avalanche events, and (iii) transects  along the entire  study area to reconstruct overall forest structure and dynamics. Mortality and establishment dates, growth patterns, and scar dates were used in  each  case.  The  frequency  and  magnitude  of  wind  blowdown  events  was  highly  variable.  Pre-blowdown structure of the forest and wind intensity determined disturbance severity, leading to diverse post-blowdown structures in the regeneration patches. Avalanches  followed blowdown events, but older events might have taken place as well. Their impact was larger at thehighest elevation blowdown patches. The resulting  stand structure  exhibited  a  multimodal  age  distribution  with  many  release  events  depicting  the  past  multipledisturbance  events.  This  study  represents  the  first report  of  wind  blowdown  avalanche  interaction  for Nothofagus forests in Patagonia.
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