INIBIOMA   20415
INSTITUTO DE INVESTIGACIONES EN BIODIVERSIDAD Y MEDIOAMBIENTE
Unidad Ejecutora - UE
artículos
Título:
Drought-induced mortality affects understory vegetation: release after death
Autor/es:
SUAREZ, MARIA LAURA; SASAL, YAMILA
Revista:
ECOLOGICAL RESEARCH
Editorial:
SPRINGER TOKYO
Referencias:
Lugar: Tokyo; Año: 2012 vol. 27 p. 715 - 724
ISSN:
0912-3814
Resumen:
In recent decades, severe droughts have become
an important cause of canopy disturbance in forests, and
have shown potential to cause rapid and pronounced
vegetation shifts. Under dead canopy, undamaged
understory could influence the nature of resource limitation
for seedling growth and survival, limiting forest
regeneration. We assessed the release response of
understory vegetation after a severe drought event in
temperate forests of northern Patagonia. Growth trends
of dominant tree saplings, and changes in vegetation
biodiversity and cover were compared between droughtdead
and unaffected canopy. Nothofagus dombeyi undergo
growth release after the climatic event in affected
forests, and the response was evidenced immediately
after the disturbance. For Austrocedrus chilensis, the
growth release response was less evident, due mainly to a
difference in age structure. In the understory the release
response was barely discernable for some components.
There was a tendency towards higher cover of the shrub
layer in the understory of drought-affected forests, and
an important presence of the exotic shrub Rosa rubiginosa.
However, the clearest biotic response following
drought mortality was the release in growth of understory
dominant tree component. Those results strongly
suggest that the environment under drought-dead canopy,
and the die-off in woody sapling cohorts in a selfthinning
process, could favor crown expansion and
growth release of understory species that could help
predict future forest trajectories in the context of the
influence of climatic extreme events.