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• 1. [Article] Effect of riparian areas on the ecological condition of small, perennial streams in agricultural landscapes of the Willamette Valley : research plan, June 1997

  Little research has been directed toward determining the status and ecological role of riparian areas in agricultural landscapes of the Willamette Valley, Oregon. A research project has been designed to ...

  Citation × Citation Citation Abstract Copy Title: Effect of riparian areas on the ecological condition of small, perennial streams in agricultural landscapes of the Willamette Valley : research plan, June 1997 Author: Moser, Thomas J., Schuft, Michael J., Wigington, P.J., Herlihy, Alan T., Van Sickle, John, Kaufmann, Phillip R., McAllister, Lynne S. Little research has been directed toward determining the status and ecological role of riparian areas in agricultural landscapes of the Willamette Valley, Oregon. A research project has been designed to contribute to the development and evaluation of alternative future scenarios and to improve the basic understanding of the role of riparian areas on the ecological condition of small, perennial streams in agricultural landscapes of the Willamette Valley. The objectives of the research are: (1) to quantify relationships between riparian attributes at varying spatial scales and stream ecological condition, and (2) to estimate the influence of selected riparian area-agricultural configurations on the indicators of stream ecological condition. To address these objectives, remotely-sensed imagery (aerial photography and thematic mapper satellite imagery) will be used to quantify land cover at multiple spatial scales (i.e., stream reach, stream network, watershed), from which riparian vegetation function, land use stressor, and stream network structure indicators (i.e., potential explanatory variables) are derived for 41 study watersheds. Title: Effect of riparian areas on the ecological condition of small, perennial streams in agricultural landscapes of the Willamette Valley : research plan, June 1997 Author: Moser, Thomas J., Schuft, Michael J., Wigington, P.J., Herlihy, Alan T., Van Sickle, John, Kaufmann, Phillip R., McAllister, Lynne S. Little research has been directed toward determining the status and ecological role of riparian areas in agricultural landscapes of the Willamette Valley, Oregon. A research project has been designed to contribute to the development and evaluation of alternative future scenarios and to improve the basic understanding of the role of riparian areas on the ecological condition of small, perennial streams in agricultural landscapes of the Willamette Valley. The objectives of the research are: (1) to quantify relationships between riparian attributes at varying spatial scales and stream ecological condition, and (2) to estimate the influence of selected riparian area-agricultural configurations on the indicators of stream ecological condition. To address these objectives, remotely-sensed imagery (aerial photography and thematic mapper satellite imagery) will be used to quantify land cover at multiple spatial scales (i.e., stream reach, stream network, watershed), from which riparian vegetation function, land use stressor, and stream network structure indicators (i.e., potential explanatory variables) are derived for 41 study watersheds. Close

• 2. [Article] Vegetation characterization of three contrasting riparian areas : Williamette Valley, Oregon

  Much of the native riparian vegetation of the Willamette Valley, Oregon, has been replaced with agricultural crops or invasive non-native plant species. Detailed information about current Willamette Valley ...

  Citation × Citation Citation Abstract Copy Title: Vegetation characterization of three contrasting riparian areas : Williamette Valley, Oregon Author: McAllister, Lynne S., Dwire, Kathleen A., Griffith, Stephen M. Much of the native riparian vegetation of the Willamette Valley, Oregon, has been replaced with agricultural crops or invasive non-native plant species. Detailed information about current Willamette Valley riparian vegetation is generally lacking. Plant specie composition data are useful in a variety of applications, including condition assessment, environmental monitoring and restoration planning. The objective of this study was to characterize the vegetation of three contrasting riparian sites occurring in the Willamette Valley. W determined plant species composition and abundance at a non-cultivated herbaceous site and a cultivated site, both located along Lake Creek, an intermittent stream, and at a forested site located along the Calapooia River, a perennial stream. All sites were adjacent to intensively-managed perennial ryegrass seed production fields. Crop agriculture strongly encroached on the Lake Creek sites, whereas the Calapooia site had received little encroachment from agricultural coversion. At Lake Creek, we inventoried 32 species at the non-cultivated herbaceous site and 18 species at the cultivated site, most of which were non-native. The cultivated site was dominated by wetland-adapted species in the area closest to the creek where perennial ryegrass was absent. Approximately half of the species at the non-cultivated herbaceous site were facultative upland species, and the site was dominated by introduced pasture grasses. In contrast, the 53 species inventoried at the forested site were mostly native and wetland-adapted. The forested site was dominated by Poplus balsamifera ssp, trichocarap T. & G., Pseudotsuga menziessii (Mirbel) Franco, and Acer macrophyllum Pursh, with extensive shrub and herbaceous strata. Results show a range of vegetative conditions found in riparian areas of the Willamette Valley and reflect the influence of differing hydrologic regimes and agricultural impacts. Title: Vegetation characterization of three contrasting riparian areas : Williamette Valley, Oregon Author: McAllister, Lynne S., Dwire, Kathleen A., Griffith, Stephen M. Much of the native riparian vegetation of the Willamette Valley, Oregon, has been replaced with agricultural crops or invasive non-native plant species. Detailed information about current Willamette Valley riparian vegetation is generally lacking. Plant specie composition data are useful in a variety of applications, including condition assessment, environmental monitoring and restoration planning. The objective of this study was to characterize the vegetation of three contrasting riparian sites occurring in the Willamette Valley. W determined plant species composition and abundance at a non-cultivated herbaceous site and a cultivated site, both located along Lake Creek, an intermittent stream, and at a forested site located along the Calapooia River, a perennial stream. All sites were adjacent to intensively-managed perennial ryegrass seed production fields. Crop agriculture strongly encroached on the Lake Creek sites, whereas the Calapooia site had received little encroachment from agricultural coversion. At Lake Creek, we inventoried 32 species at the non-cultivated herbaceous site and 18 species at the cultivated site, most of which were non-native. The cultivated site was dominated by wetland-adapted species in the area closest to the creek where perennial ryegrass was absent. Approximately half of the species at the non-cultivated herbaceous site were facultative upland species, and the site was dominated by introduced pasture grasses. In contrast, the 53 species inventoried at the forested site were mostly native and wetland-adapted. The forested site was dominated by Poplus balsamifera ssp, trichocarap T. & G., Pseudotsuga menziessii (Mirbel) Franco, and Acer macrophyllum Pursh, with extensive shrub and herbaceous strata. Results show a range of vegetative conditions found in riparian areas of the Willamette Valley and reflect the influence of differing hydrologic regimes and agricultural impacts. Close