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Bastviken, D.T., N.F. Caraco, and J.J. Cole, 1998. Experimental Measurements of
Zebra Mussel (Dreissena polymorpha) Impacts on Phytoplankton Community Composition.
Uppsala University
Reprinted with permission from Freshwater
Biology (1998) 39: 375-386
Experimental Measurements of Zebra Mussel (Dreissena
polymorpha) Impacts on Phytoplankton Community Composition
- To investigate direct effects of zebra mussel (Dreissena
polymorpha) feeding activities
on phytoplankton community composition, short-term microcosm experiments were performed in
natural water with complex phytoplankton communities. Both gross effects (without
resuspension of mussel excretions) and net effects (with resuspension) were studied.
- Gross clearance rates were not selective; essentially all taxa
were removed at similar rates ranging from 24 to 63 mL mussel -1 h -l
. Net clearance rates were highly selective; different plankton taxa were removed at very
different rates, ranging from 12 to 83% of the gross rates, leading to consistent changes
in the phytoplankton community composition. Thus, although zebra mussels can cause most
phytoplankton to decline, there is considerable variation among taxa in either
pre-digestive selection or post digestive survival.
- The direct, short-term effects of zebra mussels on phytoplankton
community composition are consistent with some of the major changes observed in the Hudson
River since establishment of zebra mussels.
- We show, with simple calculations, how zebra mussel filtration
rate, its selective efficiency on various taxa, and phytoplankton growth rates interact to
produce changes in the phytoplankton composition.
Entire Paper
Contact: Nina F. Caraco, Institute of Ecosystem Studies, Millbrook, NY 12545
www.blackwell-science.com/
Keywords: Zebra_mussel, Ecological_interactions, Basic_biology, Environmental_impacts
Product Type: Research,
Impact
User Type: Resource_management
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