Environmental constraints on Didymosphenia geminata occurrence and bloom formation in Canadian Rocky Mountain lotic systems

A study of Didymosphenia geminata, a diatom known for forming unsightly blooms in freshwater systems, found that while the organism is widespread across Canadian Rocky Mountain Parks, bloom formation is driven by local rather than regional factors. The research detected D. geminata at 88% of sampled sites, with 34% exhibiting visible blooms. Contrary to expectations, no environmental thresholds were identified for bloom development, though cell abundance was negatively correlated with stream velocity, stream order, and total phosphorus concentration. Temperature played a significant role in stalk abundance when blooms were present but showed a negative relationship with ash-free dry mass when blooms were absent. The study employed generalized linear models to analyze 76 sites across the parks, providing insights into the complex environmental constraints shaping D. geminata dynamics.

Jackson, L. J., Corbett, L., & Scrimgeour, G. (2016). Environmental constraints on Didymosphenia geminata occurrence and bloom formation in Canadian Rocky Mountain lotic systems. Canadian Journal of Fisheries and Aquatic Sciences, 73(6), 964–972. https://doi.org/10.1139/cjfas-2015-0361