Producción CyT
IAL-IPA-2022-Abstract-book - Vegetation and climate evolution in Central Isla Grande de Chiloé (42°S) during the last glacial maximum and the last glacial termination
Congreso
Fecha:
2022Editorial y Lugar de Edición:
IAL-IPAResumen *
Northwestern Patagonia (40°-44°S) has been the focus of numerous paleoenvironmentalinvestigations on the glacial, vegetation, and climate history during the Last Glacial Maximum(LGM) and the Last Glacial Termination (LGT) since the mid-20th century. Few studies,however, have examined in detail the transition through the LGM, LGT, and the currentinterglacial along a time continuum using lake sediment cores. Lago Auquilda (42°22’ S,73°49’ W, 150 m.a.s.l.) is a small closed-basin lake located in central Isla Grande de Chiloé,ideal for examining the paleovegetation, natural disturbance regimes (paleofires and eruptivevolcanic activity), and climate evolution during and since the LGM. In this study, we presenta multidecadally resolved pollen record that spans the ~19000 - 9000 cal yr BP interval andshows the continuous presence of closed-canopy temperate forests initially dominated byNothofagus, followed by diversified Myrtaceae-dominated forests, mixed forests with theconifer Podocarpus nubigena, and a sudden irruption of Weinmannia trichosperma togetherwith an increase in macroscopic charcoal. The early Holocene shows a forest dominatedby Nothofagus and Weinmannia trichosperma, lacking cold-tolerant hygrophilous conifers.Unlike the majority of records in the region, our results show persistence of dense Nothofagusdominatedforests with low variability during the final portion of LGM and the initial phaseof the LGT. This was followed by abrupt millennial-scale changes of the paleovegetation,natural disturbance regimes (paleofires and explosive volcanism), and hydroclimate troughLGT into the early Holocene. We will discuss details on the composition, timing, rates,and direction of changes in the paleovegetation and fire history at local scale, and theirimplications at regional and hemispheric scale. Información suministrada por el agente en SIGEVAPalabras Clave
PALEOECOLOGÍAPATAGONIALAGO AUQUILDA