Skip to main content
U.S. flag

An official website of the United States government

Effects of altered temperature and precipitation on desert protozoa associated with biological soil crusts

January 1, 2006

Biological soil crusts are diverse assemblages of bacteria, cyanobacteria, algae, fungi, lichens, and mosses that cover much of arid land soils. The objective of this study was to quantify protozoa associated with biological soil crusts and test the response of protozoa to increased temperature and precipitation as is predicted by some global climate models. Protozoa were more abundant when associated with cyanobacteria/lichen crusts than with cyanobacteria crusts alone. Amoebae, flagellates, and ciliates originating from the Colorado Plateau desert (cool desert, primarily winter precipitation) declined 50-, 10-, and 100-fold, respectively, when moved in field mesocosms to the Chihuahuan Desert (hot desert, primarily summer rain). However, this was not observed in protozoa collected from the Chihuahuan Desert and moved to the Sonoran desert (hot desert, also summer rain, but warmer than Chihuahuan Desert). Protozoa in culture began to encyst at 37??C. Cysts survived the upper end of daily temperatures (37-55??C), and could be stimulated to excyst if temperatures were reduced to 15??C or lower. Results from this study suggest that cool desert protozoa are influenced negatively by increased summer precipitation during excessive summer temperatures, and that desert protozoa may be adapted to a specific desert's temperature and precipitation regime. ?? 2006 by the International Society of Protistologists.

Citation Information

Publication Year 2006
Title Effects of altered temperature and precipitation on desert protozoa associated with biological soil crusts
DOI 10.1111/j.1550-7408.2006.00134.x
Authors B.J. Darby, D.C. Housman, A.M. Zaki, Y. Shamout, S.M. Adl, J. Belnap, D.A. Neher
Publication Type Article
Publication Subtype Journal Article
Series Title Journal of Eukaryotic Microbiology
Series Number
Index ID 70028846
Record Source USGS Publications Warehouse
USGS Organization