title: Combatting cyanobacteria with hydrogen peroxide: a laboratory study on the consequences for phytoplankton community and diversity.
abstract: Experiments with different phytoplankton densities in lake samples showed that a high biomass increases the rate of hydrogen peroxide (HP) degradation and decreases the effectiveness of HP in the selective suppression of dominant cyanobacteria. However, selective application of HP requires usage of low doses only, accordingly this defines the limits for use in lake mitigation. To acquire insight into the impact of HP on other phytoplankton species, we have followed the succession of three phytoplankton groups in lake samples that were treated with different concentrations of HP using a taxa-specific fluorescence emission test. This fast assay reports relatively well on coarse changes in the phytoplankton community; the measured data and the counts from microscopical analysis of the phytoplankton matched quite well. The test was used to pursue HP application in a Planktothrix agardhii-dominated lake sample and displayed a promising shift in the phytoplankton community in only a few weeks. From a low-diversity community, a change to a status with a significantly higher diversity and increased abundance of eukaryotic phytoplankton species was established. Experiments in which treated samples were re-inoculated with original P. agardhii-rich lake water demonstrated prolonged suppression of cyanobacteria, and displayed a remarkable stability of the newly developed post-HP treatment state of the phytoplankton community.
authors.affiliation: Department of Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam Amsterdam, Netherlands.
authors.forename: Erik F J
authors.initials: EF
authors.lastname: Weenink
authors.affiliation: Department of Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam Amsterdam, Netherlands ; Wetsus, Center of Excellence for Sustainable Water Technology Leeuwarden, Netherlands.
authors.forename: Veerle M
authors.initials: VM
authors.lastname: Luimstra
authors.affiliation: Department of Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam Amsterdam, Netherlands ; Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW) Wageningen, Netherlands.
authors.forename: Jasper M
authors.initials: JM
authors.lastname: Schuurmans
authors.affiliation: Phytoplankton Expertise Center, Koeman en Bijkerk Haren, Netherlands.
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Van Herk
authors.affiliation: Department of Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam Amsterdam, Netherlands.
authors.forename: Petra M
authors.initials: PM
authors.lastname: Visser
authors.affiliation: Department of Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam Amsterdam, Netherlands.
authors.forename: Hans C P
authors.initials: HC
authors.lastname: Matthijs
keywords: biodiversity; harmful cyanobacteria; hydrogen peroxide; lake mitigation; phytoplankton (Planktothrix agardhii)