Authors: Andy L Rost Christian H Fritsen Clinton J Davis
Publish Date: 2011/02/22
Volume: 665, Issue: 1, Pages: 157-167
Abstract
The freshwater stalked diatom Didymosphenia geminata has increased its proliferation in new and native ranges with the potential for significant ecological impacts to streams around the world Uncertainty remains regarding the water chemistry in which D geminata thrives despite recent advances in the understanding of its suitable physical habitat Stream surveys were conducted in the central and the northern Sierra Nevada CA USA to determine whether D geminata distribution patterns were related to water chemistry and bedrock geology Surveys included measurements of physical chemical and biological parameters from 50 stream reaches in 35 different streams The water chemistry variable percent Ca2+ P 0001 provided the best fit models binary logistic regression AUC 084 for predicting the presence of D geminata in Sierra Nevada streams Other significant water chemistry predictors included the percent SO4 2− and Mg2+ concentrations The bedrock geology variable percent metasedimentary rock in a watershed P 0001 provided the best fit model binary logistic regression AUC 077 for predicting the presence of D geminata This study further defines the environmental conditions in which D geminata thrives provides insight into D geminata ecophsyiology and will help refine current distribution and risk assessment modelsWe would like to acknowledge the funding support from the Division of Earth and Ecosystem Sciences the Truckee River Monitoring Program at the Desert Research Institute Reno NV and The Graduate School Association of the University of Nevada Reno We would also like to thank Jeramie Memmott Eric Wirthlin Tamara Cooley and Betsy Kreidberg of the Systems Microbial Ecology Laboratory at the Desert Research Institute Reno Nevada for assistance with laboratory and field work We would also like to thank Tyler Grifton and Jack Childress for assistance with the GIS work and helpful reviews from Don Sada Alison Murray Ron Hersey Julie Stoughton and Lisa Wable
Keywords: