Title page for ETD etd-09052009-040600
|Type of Document
||Ehrman, Terrence Patrick
||The use of corn pollen and glass beads to estimate fine particulate organic matter retention
||Master of Science
|Webster, Jackson R.
|Benfield, Ernest Fredrick
|Buikema, Arthur L. Jr.
|Date of Defense
Corn pollen and glass beads were used as surrogates of
natural fine particulate organic matter (FPOM). These
particles were released into ten streams in three different
physiographic regions, Appalachian Mountains, Rocky
Mountains, and Central Plains, within the United States.
Mean travel distance for corn pollen was 121 m and that for
glass beads 40 m. Rates of deposition through the water
column for both particles were 0.484 mm/sec and 0.643
mm/sec, respectively. This empirically derived deposition
velocity was only a fraction of the still water fall
velocity. Hydraulic parameters indicate that flow
conditions at the stream bed prevent establishment of a
laminar sublayer. As a result, corn pollen and glass beads
should be entrained and moved as bed- or suspended load.
Gradient was the single best stream characteristic to
explain variation in retention rates for both corn pollen
and glass beads. Based on deposition velocities, estimates
of benthic FPOM turnover times ranged from 20 hours to 8.3 days, rate of FPOM downstream movement was 1-24 m/d, and
carbon turnover length was 1-24 km.
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