Channel Adjustments, Floodplain Changes and Riparian Ecosystems of the Middle Ebro River: Assessment and Management

Abstract

In the middle Ebro River there is a 346 km reach, between Logroño and La Zaida, consisting of a free meandering channel on a wide floodplain. This reach contains a discontinuous riparian corridor, including valuable riparian forests and oxbow lakes. During the last 80 years this channel has witnessed substantial changes in channel morphology, area of bars, riparian vegetation and floodplain uses. The sinuosity growth, migrations and meander cut-offs have been frequent. There has been a progressive and significant decrease of both the area covered by water and the gravel bars without plant colonization. As a result of this, the riparian corridor width has been dramatically reduced for the benefit of human uses. The deceleration and nearly elimination of the Ebro channel free meander dynamics represents an important natural heritage loss. Dams, changes in land-use throughout the basin and river flood defences that restrict the channel have altered the system behaviour, which urgently needs a management plan combining both improvements and risk reduction.