The capacity of native fish and a freshwater mussel species to control suspended solids in wastewater stabilization ponds

Stocking herbivorous aquatic organisms in wastewater treatment ponds specifically to control phytoplankton biomass and reduce suspended solids can provide small, rural communities with inexpensive, secondary wastewater treatment. The capability of several native fish species and the freshwater mussel, <i>Elliptio complanata</i>, to reduce suspended solids and phytoplankton was compared in laboratory and field enclosure experiments. Fathead minnows (<i>Pimephales promelas</i>), gizzard shad (<i>Dorosoma cepedianum</i>), and the common carp (<i>Cyprinus carpio</i>) had either no effect, or significantly increased suspended solids levels. None of the fish species consistently reduced concentrations of typical wastewater algal taxa. The ineffectiveness of fish was attributed to numerous algal characteristics such as cell size, shape, relative abundance, resistance to digestion, and palatability. In contrast, <i>E. complanata</i> consistently and substantially reduced both suspended solids and algae concentrations in wastewater. Small-sized algae and suspended particles were either directly assimilated, or removed from suspension as pseudofeces, further promoting clarification. The proportion of suspended solids and algae concentrations removed per individual mussel declined with increasing densities of mussels. Declines in suspended solids and algae attributable to mussel filtration were best described by semilogarithmic regression equations. Mean filtration rate of <i>E. complanata</i> ranged from 53 ml/h/mussel for colonial blue-green algae, to 134 ml/h/mussel for smaller green algae. The results of this study suggest that freshwater mussels can effectively control suspended solids and algae in eutrophic environments.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Fisheries and Wildlife Sciences

Department dc:contributor.department

Fisheries and Wildlife Sciences

Grantor dc:publisher

Virginia Polytechnic Institute and State University

Year dc:date.issued

1989

Author dc:creator

• Zimmerman, Mark P.

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en_US

Handle dc:identifier.uri

http://hdl.handle.net/10919/52097

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/52097