@proceedings {5161, title = {Airborne pollen along an elevation gradient}, journal = {5th European Symposium on Aerobiology}, volume = {Krakow}, year = {2012}, note = {ID: 6266; ID: 8647; ID: 152}, month = {2012}, abstract = {We studied airborne pollen along the highest elevation gradient in Greece (2917 m), on Mt Olympos National Park. Our aim was to identify locally prevailing circulation patterns in terms of pollen quantity, quality and temporal availability, and examine the match between airborne pollen fingerprints and taxa distribution along the elevation gradient. Air samples were collected every 10 days within the period March to October using a portable Hirst-type volumetric trap. During each sampling day 12 samples from different altitudes were taken, each lasting 20 min. For four of the stations, sampling was done twice during the day, one in the morning, while ascending, and one in the afternoon, while descending. Thirty-five taxa were found contributing pollen in the study area. For half of them, participation to the total pollen load was low (<0.5\%); the remaining 18 taxa, considered as main pollen taxa, accounted for 99.1\% of all pollen recorded in the study area over the entire period and elevation range. Most abundantly represented were Pinaceae (32\%), Quercus (24\%), Urticaceae (18\%), Cupressaceae (6\%) and Poaceae (5\%); the first two make up 55\% of the total yearly concentration. Maximum daily pollen concentrations for the majority of these taxa (14) were recorded at low elevation stations (<1000 m). The main pollen season starts in March and ends in October. It peaks from early April to late July, when at least pollen from 15 of the 18 main taxa is in the air. The longest pollen seasons correspond to Asteroideae, Poaceae, Plantago and Pinaceae, whereas the shortest to Ambrosia and Cannabaceae. There is a pronounced decrease of the duration of the pollen season with elevation. The number of main pollen taxa also decreased with elevation and so did the concentration of airborne pollen produced by lowland taxa (in six out of seven); in contrast for only two of the other taxa (11), the latter relationship was significant. Our results suggest a limited movement of pollen grains beyond the elevation range, within which they are produced, what implies limited mixing of air-masses along the elevation gradient of Mt Olympos. We estimated the number of main taxa represented in the airborne pollen to decrease by approximately 4 for every 1000 m of elevation increase, whereas the average duration of the species pollen seasons to decrease by 3 days for every 100 m of elevation increase; taking into consideration the lapse rate, this corresponds to a 5-day decrease of the average pollen season for every degree (Celsius) of temperature decrease.}, author = {Charalampopoulos, A and Damialis, A and Leontidou, K and Symeonidou, A and Halley, J.M and D. Vokou} }