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An Interregional Comparison of Channel Structure, Transient Storage and Nutrient Uptake in Streams Draining Managed and Old Growth Watersheds
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Abstract: | We compared stream channel structure (width, depth, substrate composition) and riparian canopy with transient storage and nutrient uptake in 32 streams draining old-growth and managed watersheds in the Appalachian Mountains (North Carolina), Ouachita Mountains (Arkansas), Cascade Range (Oregon) and coastal redwoods (California). Despite distinct stream differences among geographic regions, there were consistent trends in channel structure and riparian canopy in streams draining old-growth and managed watersheds. No significant differences were found in stream width, depth, or streambed area, but streams draining managed watersheds had less riparian and smaller median substrate sizes. Transient storage was calculated as the difference between predicted and actual chloride transport, and nutrient uptake was estimated from the downstream depletion of added nutrients. Transient storage (As) was greatest in the redwoods streams, followed by Cascade, Ouachita and Appalachian streams. In all regions, streams draining managed watersheds had less As than streams draining old-growth watersheds. Phosphate uptake did not exhibit strong regional or treatment differences, but was significantly longer where riparian canopy and As were greater. Ammonium uptake was significantly different among regions, longer in streams draining old-growth watershed, and inversely correlated with riparian canopy, channel area, and As. |
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Citation: | Hill, B. H., F. H. Mccormick, B. C. Harvey, S. L. Johnson, and M. C. Warren. An Interregional Comparison of Channel Structure, Transient Storage and Nutrient Uptake in Streams Draining Managed and Old Growth Watersheds. Presented at North American Benthological Society, Athens, GA, May 27-31, 2003. |
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Contact: |
Linda Ransick - (513) 569-7395 or ransick.linda@epa.gov
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Division: |
Ecological Exposure Research Division |
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Branch: |
Ecosystems Research Branch |
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Product Type: |
Abstrct/Oral |
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Presented: |
05/27/2003 |
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