Jackson, LelandCorbett, Lisa Maureen2013-03-262013-06-152013-03-262013Corbett, L. M. (2013). Relationships between Didymosphenia geminata occurrence, blooms and environmental conditions (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/27607http://hdl.handle.net/11023/575Algal blooms have often been attributed to an increase of nutrients that results in increases in maximum algal biomass. However, Didymosphenia geminata, a diatom blooming in Canadian streams for the past 30 years, blooms in oligotrophic streams. I examined the environmental conditions and algal nutrient use of low nutrient Rocky Mountain streams where D. geminata experiences significant blooms. I determined that the local variables of low water velocity, low water temperature and low concentrations of total phosphorus were important predictors of D. geminata cell abundance. The conditions that promote algal blooms were not clearly established, as occurrence of blooms was not strongly related to an increase or decrease in phosphorus concentration. These results suggest there may be a complex combination of nutrients and environmental conditions that promote blooms that were not identified within the scope of this study. However, as I had no consistent conditions that related to the presence of D. geminata blooms, an alternative hypothesis is that there may be multiple strains of D. geminata. There may be strains that are able to bloom and others that cannot. This study has opened many doors into further work that needs to be conducted on D. geminata before we can fully understand the factors that cause this diatom to create noxious algal blooms.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.Fisheries and AquacultureEcologyLimnologyDidymosphenia geminataalgaeinvasive speciesRiverdiatomnuisance bloomlow phosphorusnutrient diffusing substratamaster thesishttp://dx.doi.org/10.11575/PRISM/27607