PARTICULATE ORGANIC MATTER DYNAMICS IN EPHEMERAL TRIBUTARIES OF A CENTRAL APPALACHIAN STREAM
Headwater ephemeral tributaries are external interfaces between uplands and downstream waters. Terrestrial particulate organic matter (POM) is important in fueling aquatic ecosystems, however the extent to which ephemeral tributaries are functionally connected to downstream waters through fluvial transport of POM has been little studied. Hydrology and deposition of leaf and wood, and surrogate transport (Ginkgo leaves and dowels) were measured over month-long intervals through the winter and spring seasons (6 months) in 10 ephemeral tributaries (1.3 – 5.4 ha) in eastern Kentucky. Leaf deposition and surrogate transport varied over time, reflecting the seasonality of litterfall and runoff. Leaf deposition was higher in December than February and May but did not differ from January, March, and April. Mean percent of leaf transport from the ephemeral tributaries was highest in April (3.6% per day) and lowest in February (2.5%) and May (2%). Wood deposition and transport had similar patterns. No POM measures were related to flow duration. Ephemeral tributaries are functionally connected to downstream waters through POM storage and subsequent release that is timed when POM is often limited in downstream waters.
Ken Fritz (Primary Presenter/Author), United States Environmental Protection Agency, firstname.lastname@example.org;
Gregory Pond ( Co-Presenter/Co-Author), USEPA, Region 2, Office of Monitoring and Assessment, email@example.com;
Brent Johnson ( Co-Presenter/Co-Author), USEPA, firstname.lastname@example.org;