The Argentinean modern Pollen Database (32º - 52º)

PRIETO, A. R.; MANCINI, M. V.; PAEZ, M. M.; SCHÄBITZ, F.; STUTZ, S; TONELLO, M. S.; VILANOVA, I.

Granada

Congreso; 11º International Palynological Congress; 2004

The modern pollen, vegetation and climate relationship for the Extra-Andean temperate Argentina (between 32º and 53º, lat. S) has been examined using isopollen maps and scatter and percentages diagrams. These analyses are based on an array of 500 modern pollen samples. Data are collected mainly from soil and there are representatives in all of the major vegetation and climate zones. The main pollen taxa are Poaceae, Asteraceae subf. Asteraceae, Asteraceae subf. Cichoroideae, Chenopodiaceae, Cyperaceae, Caryophyllaceae, Apiaceae, Rosaceae, Verbenaceae, Fabaceae, Brassicaceae, Nassauvia, Colliguaja, Lycium, Ephedra, Larrea, Prosopis, Schinus, Condalia, Monttea, Capparis, and extra-regional pollen (Nothofagus, Austrocedrus and Araucari). Modern distribution of percentages and isopollen maps of the main pollen types accurately reflects taxa abundance and the major phytogeographic units: Pampa grasslands, Espinal (xerophytic woodlands), Monte (xerophytic shrublands), Patagonian steppe, Grass steppe, Upper Andean (grass and shrub steppe). Poaceae and Asteraceae suf. Asteroideae pollen are widely distributed since Chenopodiacae show maximum percentages in arid and semiarid regions. In contrasts, Cyperaceae illustrate sub-humid and humid areas. Different shrubby pollen type assemblages characterize the Espinal, Monte and Patagonian steppe. We find significant correlations between modern mean annual temperatures and mean annual precipitation and pollen data, which suggest the potential of this database for quantitative climate reconstructions.