Nigrospora sphaerica was the major component in the airspora of three
urban outdoor sites. Less frequent fungi included Alternaria and Clado
sporium, and Curvularia which was represented by many species. Daily s
pore load showed a single peak at 10.00 h, dominated by N. sphaerica.
This was replaced by Penicillium lapidosum as the dominant spore type
at higher altitudes.