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The Arctic Tundra!. Hyporheic and Parafluvial Zones in…. The hydraulic characteristics and geochemistry of hyporheic and parafluvial zones in Arctic tundra streams, north slope, Alaska. Edwarson et al. (2003): Advances in Water Resources.
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The Arctic Tundra! Hyporheic and Parafluvial Zones in…
The hydraulic characteristics and geochemistry of hyporheic and parafluvial zones in Arctic tundra streams, north slope, Alaska Edwarson et al. (2003): Advances in Water Resources
Purpose: Investigate the hydrologic and chemical dynamics of hyporheic and parafluvial zones in Arctic tundra streams Importance: Essentially no information on Arctic streams • First comprehensive description of hyporheic and parafluvial zones in Arctic tundra streams • Continuous permafrost • Limit the importance of hyporheic processes?
Scope of Work • 17 conservative tracer additions on 7 streams from 1994-1996 • Stream reaches varied greatly • Characterize in-stream hydrologic parameters using hyporheic samplers and OTIS-P simulations • Biogeochemical and nutrient processing in hyporheic and parafluvial zones
Background: Definitions and Key Concepts • Transient storage zones • Parafluvial • Beaded stream • Importance of hyporheic and parafluvial zones • 3 key factors that control water movement in these zones • DO in the hyporheic zone • Modeling limitations
Study Area: Kuparuk R. and Oksrukuyik Cr. fertilized Kupa Kupa Mouth Of Kupa Oks
Whole Lotta Methods: • Hyporheic Samplers • Tracer Additions • Conservative Tracer Analysis • Solute Modeling • Vertical Hydraulic Gradient (VHG) • Nutrient Chemistry http://pubs.usgs.gov/sir/2005/5255/section4.html http://water.usgs.gov/ogw/gwrp/images/photos/rhodamineWT_injection.jpg
Results: OTIS Modeling • No significant relationship between As/A and discharge • General relationship held true • Average storage zone cross-sectional area of the Arctic streams • 43% (Range: 8 – 254%) • 32% (Range: 8 – 112%) without Imnavait Cr.
Results:Channel, Upwelling, and Downwelling Sites Transient Storage Zones
Top of Riffle Bottom of Riffle Results: Channel, Upwelling, and Downwelling Sites Parafluvial Tracer Penetration Hyporheic Hyporheic Parafluvial
Results: Channel, Upwelling, and Downwelling Sites Water Quality
Results: VHG and Temperature VHG Parafluvial zones in left and right point bars Riffle
Key Discussion Points and Conclusions • Transient storage in Arctic Streams • Similarity to temperate regions • As/A relationship not signifcant • Δmorphology and Δstage height are boss. • Importance of eddies • BUT hyporheic storage still muy importante! • Biogeochemical importance of hyporheic flowpath.
Key Discussion Points and Conclusions • Permafrost • Hyporheic flow not limited by permafrost in ice-free season • Spring ice-out (thaw) may results in much lower As/A values due to high snow-melt Q and reduced interstitial area • Water Quality • Interstitial waters served as sources of NO3, NH4, PO4, and CO2 • Interstitial temperature inversely related to VHG and residence time in hyporheic and parafluvial zones.
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