River restoration and realignment

Many rivers and streams have been impacted by artificial channel adjustments, where natural sinuosity and curvatur have changed, increasing bank erosion and channel avulsions. These changes have a detrimental effect on natural river flow regimes, habitat and community structure, affecting streambed stability, the vertical extent of streambed sediments, and the self-cleaning capacity of these systems. Successful river management and channel restoration incorporates the understanding of fluvial processes, geomorphology and, consequently, habitat diversity and species diversity.
The assessment and comparision of the species composition in altered and unaltered river sections revealed a micro- and meiofauna-dominated stream community displaying a high species diversity (> 170 protozoan and invertebrate species) in the natural flow and channel sections, compared to a much lower biodiversity in straightened channel sections.
The restoration project of the river Adur focused on creating the ability of the river to access its floodplain during a flood, restoring its natural sinuosity and curvatur, and enhancing riparian and channel boundary conditions through planting of natural riparian vegetation. In addition, in-channel features are restored that allow for the creation and maintenance of natural streambed stability. Realignment and restoration of previously altered river sections distinctly increases habitat and, consquently, biodiversity.