2007 Progress Report: Complex Interactions Between Harmful Phytoplankton and Grazers: Variation in Zebra Mussel Effects Across Nutrient GradientsEPA Grant Number: R831708
Title: Complex Interactions Between Harmful Phytoplankton and Grazers: Variation in Zebra Mussel Effects Across Nutrient Gradients
Investigators: Sarnelle, Orlando , Hamilton, Stephen , Peacor, Scott , Rose, Joan B. , Vanderploeg, Henry
Institution: Michigan State University , NOAA / GLERL
EPA Project Officer: Packard, Benjamin H
Project Period: January 1, 2006 through December 31, 2007 (Extended to December 31, 2008)
Project Period Covered by this Report: January 1, 2006 through December 31,2007
Project Amount: $454,779
RFA: Ecology and Oceanography of Harmful Algal Blooms (2004) RFA Text | Recipients Lists
Research Category: Aquatic Ecosystems , Ecosystems , Water
- Experimentally determine whether the effect of Dreissna on Microcystis aeruginosa changes direction across a broad gradient of phosphorus loading;
- Identify thresholds in P loading at which the Dreissna effect changes direction;
- Understand the mechanisms underlying the complex interaction between Dreissna and M. aeruginosa, with the explicit goal of predicting the consequences of changes in nutrient loading on harmful phytoplankton abundance in invaded habitats;
- Determine the degree to which experimental results from inland lakes are relevant to the interaction between Dreissna and M. aeruginosa in the western basin of Lake Erie
- Determine the extent to which Dreissna promotion of M. aeruginosa translates into increased levels of cyanobacterial toxin levels in the Great Lakes.
The centerpiece of the project is a set of three enclosure/mesocosm field manipulations that test the interactive effects of phosphorus availability and Dreissena on M. aeruginosa biomass and dominance. These factorial experiments will be conducted in Gull Lake and Lake Erie. The mechanistic component will include the development of a new theory of herbivore-phytoplankton interactions that can explain negative, positive and neutral effects of an herbivore on the abundance of a harmful phytoplankton species, quantification of selective grazing and per capita nutrient excretion by zebra mussels under widely varying environmental conditions, genetic characterizations of M. aeruginosa via HIP-PCR, and monitoring of cyanobacterial toxin production.
We will determine whether the effect of D. polymorpha on M. aeruginosa changes direction across a broad gradient of phosphorus loading, and if so seek to identify critical loading thresholds that can be applied in the management of invaded habitats. We expect to achieve a better general understanding of the mechanisms underlying herbivore-nutrient-phytoplankton interactions. Measurements of toxin levels will directly quantify a potentially critical threat to public health, and when coupled to genetic characterizations of Microcystis, should further our ability to predict when and where toxic blooms are likely to occur in Dreissena-infested habitats. Our research may begin to shed light on the question of why Microcystis aeruginosa appears to be uniquely responsive to Dreissena invasion relative to other phytoplankton species.
Journal Articles on this Report : 2 Displayed | Download in RIS Format
|Other project views:||All 9 publications||3 publications in selected types||All 3 journal articles|
||Knoll LB, Sarnelle O, Hamilton SK, Kissman CEH, Wilson AE, Rose JB, Morgan MR. Invasive zebra mussels (Dreissena polymorpha) increase cyanobacterial toxin concentrations in low-nutrient lakes. Canadian Journal of Fisheries and Aquatic Sciences 2008;65(3):448-455.||
||Wilson AE, Kaul RB, Sarnelle O. Growth rate consequences of coloniality in a harmful phytoplankter. PLoS One. 2010;5(1):e8679.||