INVESTIGADORES
SOTTILE Gonzalo David
congresos y reuniones científicas
Título:
Eastern Andean Patagonia (40º-51ºS) vegetation and climate variability during the Holocene related to southern westerlies fluctuations
Autor/es:
SOTTILE, G.D.; MARCOS, ALEJANDRA; BAMONTE, F.; ECHEVERRÍA, MARCOS; DE PORRAS, M. E.; TONELLO, M. S; MANCINI, M. V.; BIANCHI, M. M.
Lugar:
Goa
Reunión:
Congreso; PAGES 2nd Young Scientist Meeting; 2013
Institución organizadora:
PAGES
Resumen:
The
integration of eastern Andes Patagonian peat, lake and caves records offer the
opportunity to get a better understanding of different plant communities
response to environmental challenges at different scales. The selected fossil records
implied in this study are located between 40-43°S in western (NWP), central
(NCP) and northeastern of Patagonia (NEP) and between 49°-51°S in western (SWP)
and southcentral (SCP) of Patagonia. Since the early Holocene northern and
southern records shows similar patterns, displacing forest and grass steppe
communities eastwards and showing high fire activity. This vegetation shifts
may have been forced by weaker westerlies allowing humid air masses to reach eastward.
During the middle Holocene WNP registered short humid periods inferred by
eastern expansion of the forest communities and low fire activity meanwhile in
NCP and NEP xeric steppe communities dominate with low fire activity suggesting
arid conditions by an intensification of westerly belt. This westerlies
behavior is inferred in SWP by the development of dense forest and arid shrubs
steppes and low fire activity. Between 3000-2000yrs BP, north and south steppe
reconstructions suggest wetter conditions possibly associated to an equatorial
displacement and weakening of the westerly belt. Since the 2000 to 500yrs BP
there is a similar trend from wetter to arid conditions inferred by northern
and southern steppe sequences. After the Medieval Climatic Anomaly (last 500yrs
BP) the NEP shows palynological and charcoal evidences of wetter conditions
than the previous period meanwhile the SWP presents short periods of wetter conditions
inferred also by glaciological records.