Cyanobacteria (“bluegreen algae”) often proliferate at the same time and under similar conditions that are favourable for internal phosphorus (P) loading from lake bottom sediments. Internal loading as P released from anoxic sediment surfaces often represents the main summer P load to lakes. Because of its high biological availability, the lack of dilution, and the timing, it can have an immense effect on summer-fall water quality of a lake, reservoir, or pond.
In this workshop correlations and coincidences, as well as limnological reasoning is provided in support of the hypothesis that cyanobacteria blooms (in general and for the recently increased frequency), are related to increases in internal P loading. Both internal P loading basics and cyanobacteria background are provided and possible links between sediment released P and cyanobacteria blooms are explored.
Ways of quantifying internal load in polymictic and stratified lakes are presented, sometimes in a step-wise fashion, where missing data may be predicted by subsidiary models. Applications regarding lake quality assessment and trophic state, and an introduction into the theory of lake restoration will be provided. Each workshop topic will include a description of the theory and presentation of case studies covering US, Canadian, and European lake assessment and restoration projects listed at http://www.fwr.ca. Since the workshop was first offered, case studies have continued to support such connections. Much of this workshop is based on the recent book: Nürnberg, G.K., 2025. Lake Functioning: Internal Phosphorus Loading, Cyanobacteria, and Climate Change. CRC Press, 298 p. https://www.routledge.com/9781032294407
Presenter Gertrud K. Nürnberg, Ph.D. (McGill, Quebec) is the principal of Freshwater Research, a limnological company focusing on restoration and modeling of eutrophic lakes and reservoirs. She is specialized in internal processes in eutrophic lakes such as internal phosphorus loading and hypoxia and has more than 40 years of experience working with lake associations, governmental agencies, engineering companies and the private sector in the US, Canada, and Europe. She won several of NALMS’ prestigious awards and published more than 70 peer-reviewed papers and one book. Her published research includes comparative studies and empirical lake models on phosphorus, iron, and anoxia and on lake management techniques in numerous scientific journals. She was an associate editor of the NALMS Journal Lake and Reservoir Management, and is still actively involved in the peer-review process in many scientific journals.
Gertrud K. Nürnberg, Ph.D. (McGill, Quebec) is the principal of Freshwater Research, a limnological company focusing on restoration and modeling of eutrophic lakes and reservoirs. She is specialized in internal processes in eutrophic lakes such as internal phosphorus loading and hypoxia and has more than 40 years of experience working with lake associations, governmental agencies, engineering companies and the private sector in the US, Canada, and Europe. She won several of NALMS’ prestigious awards and published more than 70 peer-reviewed papers and one book.
Her published research includes comparative studies and empirical lake models on phosphorus, iron, and anoxia and on lake management techniques in numerous scientific journals. She was an associate editor of the NALMS Journal Lake and Reservoir Management, and is still actively involved in the peer-review process in many scientific journals.