|Shields Jr, Fletcher|
Submitted to: Federal Interagency Sedimentation Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 2/15/2006
Publication Date: 4/1/2006
Citation: Wu, W., He, Z., Wang, S.S., Shields Jr, F.D. 2006. Analysis of aquatic habitat suitability using a depth-averaged 2-D model. Proceedings, Third Federal Interagency Hydrologic Modeling Conference. April 2-6, Reno, Nevada. Advisory Committee on Water Information, Subcommittee on Hydrology, Washington, DC. CD-ROM.
Interpretive Summary: Guidelines for managing stream channels damaged by erosion often focus on either erosion control or ecology, but rarely integrate goals from these two areas. A sophisticated computer model was used to predict the effects of placing large wood structures made from downed trees on the outside of an eroding meander bend of a small, Mississippi stream on water depth, water velocity, and fish habitat quality. The model runs showed that the structures improved an index of habitat quality for a common native fish species by 82%. These findings are useful to resource managers who are attempting to select stabilization measures that are cost-effective and environmentally friendly.
Technical Abstract: Physical habitat modeling is mostly based on physical variables such as water depth, velocity, bathymetry and substrates. However, habitats and organisms in these ecosystems also reflect the influences of vegetation, pollutant transport, biochemical processes, etc. This paper presents a depth-averaged 2-D model that may be used to simulate flow, sediment transport, vegetation, water quality and ecology in aquatic systems. The model predicts the temporal variation and horizontal distribution of habitat suitability for various fish species in a river reach using the simulated flow, sediment and water quality parameters. The model has been applied to evaluate the fish habitat in a meander bend of Little Topashaw Creek, an incised, sand bed stream in northern Mississippi stabilized with structures built from downed trees. Model results showed that the constructed large wood structures can improve habitat quality as well as stabilize the eroding channel banks. The weighted usable area and overall habitat suitability index for selected native fish species were increased by the constructed structures.