HR: 1330h
AN: NB33M-02    [Abstracts]
TI: Response of Macroinvertebrate Assemblages to Experimental Additions of Coarse Woody Debri
AU: Maloney, K O
EM: malonko@auburn.edu
AF: Auburn University, Dept of Biology, Auburn, AL 36849 United States
AU: * Feminella, J W
EM: jfeminel@acesag.auburn.edu
AF: Auburn University, Dept of Biology, Auburn, AL 36849 United States
AB: Coarse woody debris (CWD) provides an important habitat for benthic macroinvertebrate assemblages in coastal plains streams, yet controlled experiments demonstrating the degree to which impaired (low-CWD) stream communities can be restored are lacking. We used field experiments to examine effects of CWD additions on benthic macroinvertebrates in 4 small sandy streams with contrasting bed stability from catchment disturbance at the Fort Benning Military Installation, Georgia, USA. We created debris dams by adding logs from pre-felled trees to 10 sites along 120-m reaches, and after 7 mo compared assemblages within debris dams (in underlying substrate) and outside of debris dams (~5 m from dams). As expected, mean macroinvertebrate density, biomass, and Shannon's H' were higher within vs outside of debris dams for 3 of the 4 streams. However, the stream with the most stable stream bed and highest amount of pre-addition CWD (which also drained the least disturbed catchment) showed opposite patterns with biomass, density, and H' being higher outside than inside the CWD additions. Our preliminary results suggest that additions of CWD in highly disturbed streams may increase benthic abundance, although similar additions to streams within relatively stable beds may have minor to no positive effects on benthos.
DE: 0400 Biogeosciences
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly