Pollen Dispersal and Deposition on the Quelccaya Ice Cap, Peru

The relatively young science of tropical ice-core palynology has proven effective in the study of paleoenvironments by its ability to produce long-term and highresolution paleoclimatic data. However, no studies thus far have investigated the basic dispersal and depositional processes of pollen on these tropical ice caps. In this study, 15 surface snow samples were taken along an east-west transect on the Quelccaya Ice Cap in southern Peru. Results show that pollen assemblages remain fairly uniform across the ice surface, suggesting a uniform mixing of the air mass and its pollen contents over the ice cap. The pollen concentrations, ranging between 17,250 and 55,400 grains/liter, are the highest ever found on a tropical or nontropical ice cap. Concentrations were highest toward the western edge of the ice cap, suggesting that the prevailing winds may have a greater influence on pollen dispersal than other diurnal winds. These results are the first step in understanding the fundamental questions of modern pollen-rain and depositional processes on a tropical ice cap, which are essential for reliable and accurate interpretation of ice-core pollen data.