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Dust storms originated primarily in the Sahara Desert severely affected the East Mediterranean mostly during winter and spring seasons. The main goal of our study addressed the qualitative and quantitative aspects of dust-associated culturable fungal communities sampled during dust events 2004-2005 in Haifa, Israel, and their comparison with the communities sampled during the adjacent clear days. The effect of particulate matter concentrations and elemental composition of the atmospheric particles on fungal communities was also estimated. Airborne fungi were collected with the Six Stage Andersen Viable Impactor. Their taxonomic identification was based mainly on morphological characteristics; one repeatedly isolated type of non-sporulated colonies was identified employing the polymerase chain reaction (PCR). During six dust events and the adjacent clear days, 98 species were collected - 79 and 32 species in dusty and clear days, respectively. The dust-associated fungal communities were significantly richer than the communities found on clear days (Wilcoxon signed-rank test, p = 0.03). Remarkable increases in concentration of airborne fungi during the dust events compared to the adjacent clear days have also been revealed. The following species were most frequently and abundantly isolated: Alternaria alternata, Aspergillus niger, Cladosporium cladosporioides, Penicillium glabrum, P. chrysogenum, Phlebia sp. (the basidiomycete species identified by PCR), Ceriporia metamorphosa (>70% of samplings); A. versicolor, C. sphaerospermum, P. aurantiogriseum, P. griseoroseum, P. purpurogenum, and Pleospora tarda (>40% of samplings). The Canonical correspondence analysis showed that the dominant environmental factors influencing the distribution of these species were a concentration of fine atmospheric particles followed by the concentration of geological elements and coarse particles. On a whole, the study revealed distinct pattern of distribution for fungi in the atmosphere of Haifa strongly influenced by Saharan dust storms. [ABSTRACT FROM AUTHOR]

Monthly dustfall samples collected in 16 sites in the Tel-Aviv urban areas, as well as those collected in 10 rural sites in Israel during several years of measurements, were analyzed for their physical properties and chemical content. Although dustfall measurements represent a very simple and crude technique the analysis of the data provides some very interesting conclusions: (a) The southwest part of Israel, which is scarcely populated, suffers from high dustfall values due to dust storm blowing from the Sahara and other arid lands to the east Mediterranean during the spring. (b) On an annual basis the natural dustfall of dust storms origin amounts to 25 to 30% of the Tel-Aviv residential area deposition or 3 to 4 tonne km mo. (c) Mapping of dustfall data within an urban region reflects fairly well the main industrial and commercial activities within the city. (d) In residential areas the inorganic water insoluble fraction of the dust is contributed by natural sources, while the organic fraction is mostly of anthropogenic origin. The inorganic water soluble fraction is spread in a uniform pattern within the city. [ABSTRACT FROM AUTHOR]