Assistant Professor Emporia State University, United States
Abstract: Streams carry nutrients, sediment and other materials into rivers, lakes, and the ocean. Streams naturally meander, and streams with low sinuosity are less likely to have basic pool-riffle features along with regular erosion and deposition patterns. As a restoration measure to a heavily eroded stream, sinuosity was increased with the addition of beaver dam analogues to introduce a meander in a 150-meter stretch of a first order stream. Upstream, a section of the stream was not restored and used as a control. There were three objectives of this restoration project: to restore the in-stream habitat for native fish and invertebrates; to reduce sediment and nutrient loads into the connected downstream river; and to restore a river–floodplain landscape typical to naturally meandering rivers. To determine the effects on the biodiversity within a stream habitat with low and restored sinuosity, we surveyed physical habitats for substrate composition, depth, width, water chemistry, and current velocity. Macroinvertebrates and fish were sampled to determine community composition shifts in response to the restoration.
Over time in this project, not only the natural landscape of a meandering river, but its function was successfully restored. The sediment load decreased, and the macroinvertebrate and fish diversity increased. The monitoring results indicated that these goals were likely achieved in the short term after the restoration. In conclusion, this study shows that stream restoration using introduced meander along with other natural techniques can be very advantageous to aquatic ecosystem health, diversity, and erosion.
