PARENT SESSION
Oral Session #47: Conservation Ecology: Aquatic.
Presiding: L. Stevens
Tuesday, August 6. 1:00 PM to 4:45 PM. Palo Verde Room, Radisson.
Analysis of potential for conservation and restoration of floodplain forests and river channels in the Willamette River, Oregon.
Gregory, Stan*,1, Hulse, David2, Ashkenas, Linda1, Wildman, Randy1, 1 Oregon State University, Corvallis, OR2 University of Oregon, Eugene, OR
ABSTRACT- Assessment of potential for both conservation and restoration of floodplain forests and river channels in a large, floodplain river requires information on fundamental ecological relationships, historical changes, and distributions of biophysical and social features along the floodplain. We present an approach for assessment of conservation and restoration opportunities based on analysis of current river conditions, historical reconstruction, and alternative scenarios for the future. We sampled fish habitat and richness in the Willamette River and determined changes in channel structure, riparian vegetation, and fish assemblages from 1850 to 1995. Current conditions of floodplain and river channels provided the basis for delineating areas of greater potential for conservation of intact floodplain systems. Degree of change from historical conditions was used to delineate potential for restoration. Patterns of human systems (population, structures, land value) were used to represent socioeconomic constraints. Areas of high ecological condition were identified for conservation. Other sites offer high restoration potential but have low social pressures, making them more suited for restoration. Areas with high human densities offer opportunities for public education about appropriate river management through day-to-day experience and examples. Other locations with high ecological potential but high social obstacles offer opportunities to lower social limitations through policy changes. Examples of site level applications and dynamic visualization of restoration potential for the Willamette River will be presented. Longitudinal patterns of conservation and restoration potential provide a basis for identifying areas adjacent to reaches with high potential so that contiguous areas of high potential habitat can be expanded. Integration of biophysical and socioeconomic properties of rivers has major implications for long-term success in river restoration.
KEY WORDS: Floodplain, River, Restoration, Conservation