Influence of dust storms on concentration and content of fungi in the atmosphere of Haifa, Israel

Dust storms originating primarily in the Saharan desert heavily affect the Eastern Mediterranean, mostly during the winter and spring season. The main goal of our study addresses the qualitative and quantitative aspects of dust-associated fungal communities sampled during dust events in the years 2004-2005 in Haifa, Israel, and their comparison with the communities sampled on 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. During six dust events and the adjacent clear days, 98 species were collected79 and 32 species in dusty and clear days, respectively. The dust-associated fungal communities were significantly richer than the communities of clear days (Wilcoxon signed-rank test, p = 0.03). Remarkable increases in the concentration of airborne fungi during the dust events compared to the adjacent clear days have been also revealed. The canonical correspondence analysis showed that the concentration of fine atmospheric particles was the dominant environmental factor influencing the distribution of most common fungal species followed by the concentration of geological elements and coarse particles. Overall, the study revealed a distinct pattern of distribution of fungi in the atmosphere of Haifa that was strongly related to Saharan dust storms.