Land use and land cover change and river adjustment

The EbroHydromorph project aims at studying the morphological changes of the middle Ebro River (between Logroño and La Zaida) in recent decades, and sediment transport in particular. In a first phase, a historical study of land use and land cover changes in the Ebro river basin to the end point of the study area is carried out, with an area up to 49,434 km², with the aim of finding out how these changes have affected the hydrogeomorphological conditions of the main river and its tributaries.

The elaboration of the cartography of the mid-20th century has been a laborious task carried out by digitalising land use and land covers (LULC) and completing it with some of the maps already drawn up previously in a few areas of the studied basin. This basin covers a very wide typology of landscapes, from Atlantic, to Mediterranean, including alpine and semiarid landscapes.

Land use and land cover distribution of the mid-20th century has been reconstructed and compared with that available in the 2014 land use and cover map, analysing in detail the modification of the active channel surfaces of the entire basin, as an indicator of the changes in flow and sediment inputs. The preliminary results show a drastic reduction of active channel surfaces, while forest, artificial and grassland areas have increased.

Additionally these land use and land use cover changes have been related to discharge evolution in those unregulated river reaches, in order to see the impact of LULC changes on flow availability.