Zebra Mussel Research Technical Notes. Influences of Zebra Mussels on Conditions

摘要

One of the concerns over the invasion of zebra mussels in the Upper MississippiRiver (UMR) system is the rapid colonization of these organisms in backwater regions with accompanying changes in water/sediment quality and habitat value. It is expected that zebra mussels will have a pronounced effect on the sediment and water column micro-environment after colonization. For instance, zebra mussels can graze seston (phytoplankton) and, because of their high densities, can filter water at tremendous rates, thereby transferring suspended particulate matter from the water column to the sediments (Reeders and de Vaate 1990). This process may have an important impact on food web dynamics, contaminant cycling, and water/sediment quality (Bruner, Fisher, and Landrum 1994; Effler and Siegfried 1994; Holland 1993; Leach 1993; Nichols and Hopkins 1993). Zebra mussel grazing also results in increased light penetration, which could affect epipelic community productivity (Griffiths 1993) and benthic trophic levels. Excretion of feces and pseudofeces on the sediment surface (Ten Winkel and Davids 1982) could, in turn, affect sediment chemistry and nutrient dynamics at the sediment-water interface. Thus, the colonization of zebra mussels on sediments in the UMR may affect ecosystem dynamics in backwater regions. This technical note summarizes research that was conducted to examine the changes in sediment and overlying water chemistry that occur due to zebra mussel colonization.