The Azores archipelago (9 islands) stretches across a sizeable longitude span, whilesitting directly on the pathway of long-range transport of airborne species over the northAtlantic ocean-namely, dusts from Africa's Sahara and Sahel, and non-naturalcontaminants from the United States' eastern seaboard. Therefore, it is an ideal platformfor watching significant deposition episodes in the area, and/or simply keeping track ofregular downward fluxes at ground level, either through conventional or unconventional(biological) air-monitoring approaches. For this purpose, thalli of the epiphytic lichensParmotrema bangii (Vain.) Hale and Parmotrema robustum (Degel.) Hale, plus outerbark from trunks of Cryptomeria japonica (Thunb. ex L.f.) D. Don-Japanese cedar –were collected in early 2003 at three sampling locations of the Pico island, Azores,Portugal. Lichens' phorophyte was the cedar, and local soils were sampled as well.Reference data on airborne particulates have been provided by a seven-wavelengthAethalometer, that continuously collects aerosols near the summit of Pico mountain(observatory: 2225 m above mean sea level; peak: 2351 m above mean sea level) inquartz-filter tapes. Following suitable handling and preparation procedures, all fieldsamples were put through instrumental neutron activation analysis (INAA; k_0-variant)for elemental assessment. The overall results indicate that: 1) the patterns of significantelemental enrichment (EF ＞10, relative to Sc) in lichen and bark samples are quitedissimilar, with lichen data reflecting more the local inputs from some characteristichuman activities, while bark appears predominantly enriched with far-ranged elementsarriving in Pico's atmosphere after long-distance transport; 2) regardless of prospectiveelemental sources-local or global, anthropogenic or natural-bark displays a moreconservative (consistent) pattern through the sampling locations; 3) not unlike earlierindications, altitude may have a negative influence in lichen enrichment, yet the presentdata seems insufficient to back up such an eventual trend.
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