INIBIOMA   20415
INSTITUTO DE INVESTIGACIONES EN BIODIVERSIDAD Y MEDIOAMBIENTE
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Fabiana imbricata shrublands: natural firebreaks in the northwestern Patagonia?
Autor/es:
GHERMANDI L., DUDINSZKY N., AND F.J. ODDI.
Lugar:
Viena, Austria
Reunión:
Congreso; European Geosciences Union; 2009
Resumen:
Geophysical Research Abstracts,
Vol. 11, EGU2009-10210, 2009
EGU General Assembly 2009
© Author(s) 2009
Fabiana imbricata shurblands: natural firebreaks in the northwestern
Patagonia?
L. Ghermandi (1), N. Dudinszky (2), and F.J. Oddi (3)
(1) INIBIOMA, CRUB-UNCo, Bariloche, Argentina , (2) INIBIOMA, CRUB-UNCo, Bariloche, Argentina , (3) INIBIOMA,
CRUB-UNCo, Bariloche, Argentina
Fire is a natural disturbance that affects different ecosystems like the Northwestern Patagonian woodland/steppe
ecotone. Here, the fire impact on the vegetation depends on the heterogeneity of the plant communities and the
environment. This includes different responses and adaptations to fire of the species present in this community.
Fabiana imbricata is a shrub characteristic of Patagonian grasslands and although its response to fire is not well
known, it generate a special landscape pattern. Direct field observation coupled with aerial photography interpretation
and remote sensing data were used to identify the vegetation pattern. From the lower to upper zones of the
hillside topographic gradient, the vegetation changes from grasslands to F. imbricata shrublands, followed by open
Austrocedrus chilensis woodland and ending in rock outcrop.We hypothesized that F. imbricata acts as a firebreak
that creates an Austocedrus chilensis refuge in the upper part of the topographic gradient. This fire line could relate
to horizontal fuel discontinuity that derives from the presence of bare soil that occurs within the F. imbricata
shrubs. If fires are not very intense, the fuel discontinuity would stop the spread of fire coming from the grassland.
In this survey we worked in one of the post-fire sites of San Ramón ranch (41º 03´19´´S and 71º01´50´´W), 30 km
east of Bariloche, Patagonia, Argentina, where we observed the above described pattern. For this site, we know of
two fire events, and the oldest occurred 36 years ago, and the second occurred 10 years ago. We also have data
regarding the F. imbricata shrubland dynamics. Dendrochronology techniques were used to determine the age of
the shrubland. We match this data with Landsat TM images coupled with aerial photography interpretation to determine
the pre and post- fire vegetation. Future studies analysing other sites where this pattern is present will be
needed to corroborate the relationship between the pattern and the fire regime at landscape scale