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Matthew McBroom, Stephen F. Austin State University, mcbroommatth@sfasu.edu (Presenter)
Yanli Zhang, Arthur Temple College of Forestry and Agriculture, zhangy2@sfasu.edu
Alex Brown, Stephen F. Austin State University, brown.alexm@gmail.com

 

Instream large woody debris (LWD) is a critical component of aquatic habitat has significant ecological value. Rivers throughout the Southeast USA have seen significant reductions in LWD due to numerous factors including de-snagging for navigation, reservoir construction, and riparian forest degradation. Unlike other regions of the USA, relatively few studies have been conducted on LWD dynamics in Southeast Rivers. LWD loadings and dynamics were determined on two rivers in Texas, the lower Sabine and lower San Antonio. These rivers represent different ecoregions and geomorphologies within the state. In the low-gradient lower Sabine, LWD dynamics were primarily governed by riparian forest structure, with the upstream inflow component being less significant. There was no evidence that Toledo Bend Reservoir is resulting in significant reductions in LWD due to lacustrine storage. In the relatively higher gradient lower San Antonio River, upstream inputs were a more significant component of the overall LWD budget. Riparian forest health is one of the key variables impacting LWD loadings in Southeast Rivers.