2022 Early Hearing Detection & Intervention Virtual Conference
March 13 - 15, 2022
6/06/2017 | 11:30 AM - 11:45 AM | QCRITICAL AS A GEOMORPHICALLY AND BIOLOGICALLY RELEVANT FLOW THRESHOLD FOR RIVER MANAGEMENT AND RESTORATION | 302A
QCRITICAL AS A GEOMORPHICALLY AND BIOLOGICALLY RELEVANT FLOW THRESHOLD FOR RIVER MANAGEMENT AND RESTORATION
The threshold discharge that initiates streambed mobilization (Qcritical) is one of the most mechanistically-important flows for geomorphic function and biological integrity in stream ecosystems. Increased exceedance of Qcritical is a dominant driver of geomorphic instability and excess benthic disturbance in urban/suburban streams (i.e. the urban disturbance regime). In one 7-y study, reference site macroinvertebrate communities during years with atypically frequent Qcritical events were more similar to sites draining watersheds with ~30% imperviousness than to reference site communities of more typical rainfall years. Using an international database of nearly 200 sites we show that Qcritical varies by several orders of magnitude as a function of streambed particle size. Qcritical in sand-dominated streams is likely to be orders of magnitude less than the 1-yr discharge, whereas Qcritical in cobble/boulder dominated streams could be much larger than the 1-yr discharge, implying that stormwater/restoration policies focused on the 1-yr (or “bankfull”) event could lack efficacy in many settings. Incorporating Qcritical into stream restoration and stormwater management can ensure that designs are tailored to the mechanisms that drive channel erosion and disturbance to the benthos.
- S31 Moving forward in flow ecology: identifying and testing key hypotheses
- C16 Restoration Ecology
- S23 Rehabilitating urban streams: perspectives from science and management
Presentation:
This presentation has not yet been uploaded.
Handouts:
Handout is not Available
Transcripts:
CART transcripts are NOT YET available, but will be posted shortly after the conference
Presenters/Authors
Robert Hawley
(), Sustainable Streams, LLC, bob.hawley@sustainablestreams.com;
ASHA DISCLOSURE:
Financial -
Nonfinancial -
Geoff Vietz
(), Streamology/University of Melbourne, geoff@streamology.com.au;
ASHA DISCLOSURE:
Financial -
Nonfinancial -
Matthew Wooten
(), Northern Kentucky Sanitation District No.1 (SD1), mwooten@sd1.org;
ASHA DISCLOSURE:
Financial -
Nonfinancial -