Ecological engineering and management practices can enhance the value of strongly human influenced navigable waterways in the EU Green Infrastructure

In Flanders (northern part of Belgium) navigable waterways (artificially created canals or canalised rivers) are mostly strongly human influenced. To facilitate navigation hydromorphological alternation are undertaken including deepening, straightening, widening, damming, dredging, water regulation and artificial shoreline embankments. In addition, moving vessels generate physical waves and currents which increase bank erosion, sediment suspension and turbidity and cause water level fluctuations. As a result, severe impacts on biodiversity along navigable waterways occur originating from habitat losses, fragmentation and physical forces. Through integrated water management, a harmony between the different users and the functions of the waterway is to be find. The poster offers some examples of ecological engineering and management practices realised in Flanders.
Ecological engineering with the construction of ecologically friendly bank stabilisations favour riparian biodiversity and can mitigate navigation effects. Furthermore, measures promoting longitudinal and lateral free migration of aquatic species are key elements for the ecological improvement of waterways.
Embankments associated with navigable waterways can have an ecological importance, especially in highly fragmented landscape with few or very small semi-natural habitats left. In Flanders, an appropriate biodiversity-orientated management is applied by, in general, differentiated (in time and in space) mowing regimes or by extensive grazing.
As a consequence, ecological engineering and management measures play a role in maintaining and enhancing ecosystem services of navigable waterways. These services include habitat provision, water purification, bank stabilisation, pest control, pollination together with cultural and recreational services.
Generally, it can be stressed that navigable waterways can function in and can be incorporated in the EU Green Infrastructure.