A European project to protect, preserve and enhance alder forests in high river stretches is presented at the CERM

Last Monday, the Ter Museum in Manlleu hosted the European Life Alnus project, which focuses on improving the conservation of the Mediterranean alder groves - the typical riverside forest on high stretches of rivers which has various ecological functions. Speakers at the event included the coordinator of the project, Jordi Camprodon, on behalf of the Forest Sciences and Technology Centre of Catalonia (CTFC); the vice-rector for Research and Knowledge Transfer of the UVic-UCC, Jordi Villà; the coordinator of the Mediterranean Rivers Studies Centre (CERM) at the UVic-UCC, Marc Ordeix; the head of the Department of Water Control and Quality at the Catalan Water Agency, Antoni Munné; the director of the Territorial Area of the Catalunya - La Pedrera Foundation, Miquel Rafa; and the Councillor for the Environment and Green Spaces of Granollers Municipal Council, Albert Camps.

Reducing regression and deterioration

The aim of the project is to reverse regression and deterioration of this riverside habitat in Catalonia, by initiatives that can be transferred to the other river basins of the Iberian Peninsula and to Mediterranean countries in general. Work to achieve this will take place in three pilot areas: the basins of the Besòs, the Alt Ter and the Alt Segre rivers. These areas include 24 Special Conservation Areas (ZEC) and 45% of the regional distribution of the alder's habitat.

The primary conservation objective is to improve legal protection for the habitat all over Catalonia, incorporating major new areas of alder groves in the Natura 2000 Network, and declaring the passage of the Ter through the Osona region a new Site of Community Importance (SCI), , as it is not at present part of the European network. To accomplish this, a cartographic study is being completed to provide the best definition of the real distribution of the habitat.

Restoration measures

The project also aims to restore the riverside forest where it has disappeared or has deteriorated. The planned restoration measures will be carried out to achieve the maximum impact with the minimum cost, enabling the habitat to reorganise itself by means of key initiatives, such increasing the river's flow rates and removing physical barriers.

The vegetation will only be actively restored when required, by planting the species native to each stretch of the river and removing exotic invasive species. The specific problems in each area will be taken into account. For example, the fragmented areas of the habitat will restore the continuity of the riverside forest by establishing centres for the reintroduction of habitat where it has disappeared, as in most of the Congost basin, and where it is highly fragmented, as on the higher stretches of the Ter and Segre rivers.

The Catalan Water Agency plans to invest up to 515,000 € in restoration projects in the upper Ter area to improve alder groves and riverside areas, and up to 15,000 € on sensors for the measurement of ecological flow rates necessary to keep the riverbank in good condition. These investments are part of the Management Plan and Measures Programme for the River Basin District of Catalonia which the Government of Catalonia approved for the sixth period, covering 2016-2021 (Decree 1/2017).

Improved governance

The Life Alnus aims to improve the governance of riverbanks, involving the various administrations, institutions and sectors involved in the management and social use of the rivers - research centres, institutions responsible for safekeeping of the territory, environmental and sports bodies, forestry associations and owners, hydroelectric and mining companies, anglers, schools, etc.  Sectoral meetings and field visits, debates, transfer days and environmental education activities will be organised to that end.

The initial results of the improved governance have been custody agreements with the owners of lands in riverside areas and industrial activities in river areas, including municipal councils and owners of livestock farms, mining companies and the hydroelectric sector. Ecological variables will be monitored in order to assess the current state of conservation of the habitat and the impact of the conservation and restoration measures: these include vascular plants, forest structure, aquatic macroinvertebrates, fish, birds, bats and semi-aquatic mammals.

Ecological importance

Alder groves are the main riverside forests in temperate Europe and much of the Mediterranean region, dominating both the river banks of headwaters and the broad alluvial plains. Spain alone accounts for 56% of the real habitat area in countries around the Mediterranean, and 14% of this is in Catalonia - a significant percentage taking into account the country's size.

Alder forests have various ecological functions associated with rivers, including flood regulation, protecting river banks from erosion, filtering diffuse pollution into rivers, providing more strategic habitats for the conservation of a large proportion of European biodiversity, acting as a microhabitat for native fish with flooded roots, as a biological corridor that connects flora and fauna populations between protected areas, etc. They are also major leisure areas, and a landscape of great beauty.

According to the European Commission, this is a habitat with a conservation status described as "unfavourable-inadequate", both in Spain and in the Mediterranean biogeographical region as a whole. The causes of recession are due to diverse factors, including the direct destruction by the occupation of the riverbank area by urban development and crops, unsustainable forestry practices, low flow levels in rivers, the degradation of vegetation and colonisation of the area by invasive plant species.

Four years of study

Life Alnus is a LIFE Nature & Biodiversity project, lasting four years until June 2021. The partners in the project are the Forest Sciences and Technology Centre of Catalonia, which is the coordinator; the Catalan Water Agency (ACA); the Balmes University Foundation, through the Mediterranean Rivers Studies Centre; Granollers Municipal Council; the Catalunya La Pedrera Foundation; and MN Consultors en Ciències de la Conservació SL. It has received co-financing from the Besòs-Tordera Consortium and cooperation from the Ebro Hydrographic Confederation, the Ministries of Territory and Sustainability, Agriculture, Livestock, Fishing and Food of the Government of Catalonia, and from the General Directorate for Water, of the Spanish Ministry of Agriculture and Fisheries, Food and the Environment.