ISSN:
1752-1688
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Architecture, Civil Engineering, Surveying
,
Geography
Notes:
: Research has demonstrated the utility of metrics based on spatial velocity gradients to characterize and describe stream habitat, with higher mean spatial gradients indicative of higher levels of physical heterogeneity and thus habitat quality. However, detailed description of the velocity field that is needed to compute these metrics is difficult to obtain. Acoustic Doppler current profilers (ADCPs) may be used to rapidly collect detailed representations of river depth and velocity fields in rivers deeper than 1 m. Such data were collected in March 2000 from cross sections of the Little Tallahatchie River, Mississippi, representing three distinct habitat types (naturally sinuous, channelized, and abandoned channel). These datasets were used to compute component velocities, vorticity, and area weighted mean vorticity (circulation). Velocities and circulation were highest in the meander, lowest in the abandoned channel, and intermediate in the channelized reach. Secondary flow, expressed as the average magnitude of the lateral (transverse) velocity divided by the total velocity, was significantly higher in the meander. The sinuous natural channel and abandoned channel displayed distinctive spatial patterns, with regions of depressed velocity consistently occurring near banks. ADCPs hold great potential as tools for the study of riverine ecosystems, but data reduction is difficult using existing software.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1752-1688.2003.tb04426.x
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