Algal diversity in North American desert soils

摘要

Clonal isolates of cyanophytes were collected from several study sites in the Dugway Proving Ground and San Rafael Sell Overlook in Utah. We identified 32 taxa belonging to 24 cyanobacterial genera. Some taxa were widely distributed, occurring in all sites. For example, the members of the filamentous cyanobacterial genera Leptolyngbya, Microcoleus, Nostoc and Trichocoleus and members of the coccoid genus Aphanocapsa were common to all sites. On the other hand, members of the cyanobacterial genus Calothrix were rarely encountered at the Dugway site but were recovered frequently from the San Rafael site. We were able to compare disturbed and undisturbed sites located close together in the San Rafael Overlook. We found that the genera Spirirestis and Cyanosarcina, were found exclusively in the undisturbed site. A number of the taxa recovered could be identified only to the genus level because they did not match previously published species descriptions. Since we have recovered both prokaryotic eukaryotic taxa new to science in our previous work, it is quite likely that some of these isolates do indeed represent new cyanobacterial species. This study is the most extensive characterization of cyanobacteria from soil crusts in a semi-arid North American deserts. It expands our knowledge of the diversity of the cyanobacterial components of North American soil crusts.