HR: 09:45h
AN: NB41F-06 INVITED     [Abstracts]
TI: A Mosaic of Riparian Landforms Determine Wood Debris Recruitment and Redistribution During Floods in a Southeastern Coastal Plain Stream
AU: * Golladay, S W
EM: sgollada@jonesctr.org
AF: J.W. Jones Ecological Research Center, Rte 2, Box 2324, Newton, GA 39870 United States
AU: Battle, J M
EM: jbattle@stroudcenter.org
AF: Stroud Water Research Center, 970 Spencer Road, Avondale, PA 19311 United States
AU: Palik, B J
EM: bpalik@fs.fed.us
AF: USDA Forest Service, 1831 Highway 169 E., Grand Rapids, MN 55744 United States
AB: In southeastern Coastal Plain streams, wood debris can be very abundant and is recruited from streamside forests. Since 1994, measurements of downed trees (species, dbh, orientation, distance from baseflow channel, and condition) were made across replicated riparian landforms in a 5th order stream. Annually, the fate of these trees was determined and newly recruited trees were noted. More constrained reaches had greatest mortality. Generally, recruitment was greatest in years with substantial floods. Tree mortality was correlated with the maximum daily flow during the period preceding surveys. This relationship was strongest for sand ridges (r²=0.942) and terraces r²=0.915). Flood characteristics also influenced debris recruitment. A 1994 flood caused by a tropical storm caused a rapid rise in stream flow. Much of the debris recruited during this flood was from toppled trees and was oriented parallel to the stream channel. A 1998 flood had more gradually rising flows with no relationship between landform and debris characteristics. These results indicate that wood recruitment dynamics in Coastal Plain streams are complex. Wood recruitment rates are controlled by cyclical variations in climate interacting with a mosaic of riparian landforms. Infrequent floods are critical in the maintenance of the instream debris pool.
DE: 1821 Floods
DE: 1824 Geomorphology (1625)
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly