HISTORIA VEGETAL RECIENTE EN PATAGONIA OCCIDENTAL. ANÁLISIS PALINOLÓGICO DE LAGUNA CEA (45º40’S, 72º14’W), COYHAIQUE, CHILE

Abstract

A palynological analysis was performed
on the sedimentary cover of Laguna Cea,
located in the subbasin of the Simpson
River in the Coyhaique region of southern
Chile. The pollen record shows a landscape
evolution from a woodland-type ecosystem
covered by Nothofagaceae (Nothofagus
antarctica/N. dombeyi) to a meadow-type
ecosystem in which low brush such as
calafate (Berberidaceae), herbaceous layers
such as different types of grasses (Poaceae),
and hydrophilic vegetation such as marsh
plants (Cyperaceae) may be found. This
structural change in vegetation occurred
approximately 120 years before present
(BP) and coincided with the middle of
the XIX Century, the epoch which marks
the beginning of colonial settlements and
the consequent clearing and livestock
grazing. The palynological record supports
the occurrence of fire through charcoal
particles in the sediments analyzed for the
aforementioned period, which suggests that
current variation in the landscape of the
region has been influenced by anthropic
action.