Poster Details
BIOLOGICAL AND ECOSYSTEM LEVEL CHANGES IN DAMMED HEADWATER STREAMS
Small dams may convert intermittent streams to perennial for water extraction. In Arkansas, 700 streams were dammed for high-volume-hydraulic fracturing water withdrawal. Increases in dam constructions may affect macroinvertebrate communities and consequently alter decomposition rates. We predicted that once intermittent headwaters would be continuous changes in dissolved oxygen, temperature, and conductivity would occur. Abiotic changes were predicted to change macroinvertebrate diversity and leaf decomposition rates. We predicted that dammed streams would have greater macroinvertebrate diversity and faster rates of leaf litter decomposition from increased macroinvertebrate processing. We deployed leaf-litter decomposition bags at three dammed and three free-flowing streams. Six benthic macroinvertebrate samples (N=24) and associated water characteristics were collected at each site. We found no significant differences in water characteristics; temperature was slightly higher in dammed (7.9?) than free-flowing streams (6.4?). Although there were no differences in macroinvertebrate richness and density, decomposition rates were faster upstream in free-flowing streams (k=0.038), but greater downstream in dammed streams (k=0.025). Hydrology shifting from intermittent to perennial may extend detritus conditioning to improve palatability. Small dams may alter decomposition in currently unidentified pathways.
Brian Staley (Primary Presenter/Author), University of Central Arkansas, bstaley2@cub.uca.edu;
Danielle Braund (Co-Presenter/Co-Author), University of Central Arkansas, dbraund1@cub.uca.edu;
Sally Entrekin (Co-Presenter/Co-Author), Virginia Tech, sallye@vt.edu;
Margaret Young (Co-Presenter/Co-Author), Hendrix College, YoungMM2@hendrix.edu;
Krishna Patel (Co-Presenter/Co-Author), Hendrix College, PatelKK@hendrix.onmicrosoft.com;
Maureen McClung (Co-Presenter/Co-Author), Hendrix College, mcclung@hendrix.edu;
Matt Moran (Co-Presenter/Co-Author), Hendrix College, Moran@hendrix.edu;