PROJECT DESCRIPTION
BACKGROUND
The Ebro Delta in Catalonia is a wetland of international importance, and is considered one of the coastal systems most vulnerable to climate change in the European Union. The delta is undergoing a loss of wetlands and rice paddies because of coastal regression, caused by diminishing fluvial sediments, which are retained in the reservoirs of the basin. The coast is retreating by more than 10 metres per year in the mouth of the delta, where 150 hectares of wetland were lost between 1957 and 2000. The problem is accentuated by the decline in the elevation of the delta, because of the rise in sea level and subsidence. About half of the delta (15 000 ha) could be affected by this phenomenon during the 21st century.
OBJECTIVES
The LIFE EBRO-ADMICLIM project planned to carry out a number of climate change adaptation and mitigation pilot actions in the Ebro Delta. It aimed to implement an integrated approach to the management of water, sediment and habitats (rice fields and wetlands), with the objectives of optimising ground elevation (through inputs of inorganic sediment and organic matter), reducing coastal erosion, increasing the accumulation (sequestration) of carbon in the soil, reducing greenhouse gas emissions, and improving water quality.
RESULTS
LIFE EBRO-ADMICLIM resulted in the implementation of a set of demonstration actions that integrated both climate change adaptation and mitigation measures in the Ebro Delta (Catalonia, Spain), an area vulnerable to sea level rise and subsidence. The integrated approach combines the management of water, sediment and habitats, and involves different social and economic actors. This acts as the starting point for a long-term integrated strategy for climate change mitigation and adaptation in the Ebro Delta area.
The project demonstrated the feasibility of restoring sediment inputs from the Ebro River's reservoirs into its delta, as well as from a water purification plant to the rice paddies, which did not affect rice productivity. Thus, an analysis of the real capacity of the river and of the irrigation network to transport sediments was performed. Moreover, the beneficiaries estimated the subsidence level of the delta and identified the areas that are most vulnerable to subsidence and sea level rise. Several tests were carried out to assess the capacity of the wetlands to retain water pollutants and to reduce greenhouse gas (GHG) emissions generated by rice paddies. Environmental benefits of the project included the reduction of waste generated in the water treatment plant (1 000 tonnes/year of sediment) and the reduction of the subsidence of the Ebro Delta (floor elevation rates of around 0.5 cm/year). The project achieved carbon sequestration rates of around 80 g/m2/year in the artificial wetlands created, as well as nitrate reduction rates up to 70%, and contaminant reduction rates of around 30%. The project team calculated reduced GHG emissions from rice paddies (8 000 – 12 000 tonnes/year of CO2 equivalent). They estimated that GHG reductions up to 90% (for methane) could be achieved following changes in agricultural practices, such as the alternate wetting and drying (AWD) water management method for rice cultivation. There was also an enhanced understanding among the project beneficiaries of the complexity of the integrated approach, and the need to avoid adverse indirect effects on Ebro Delta management arising from the many interacting factors.
The results obtained have allowed the beneficiaries to propose measures, strategies and good practices to optimise the operation of the wetlands and the agricultural practices of the rice sector. Project partners reached a large audience with their impactful dissemination actions. This helped foster networking initiatives with private companies, international agencies, universities and research groups, expert groups, and other LIFE projects.
A Climate Action Plan for the Ebro Delta was developed, with concrete and effective measures for climate change adaptation and mitigation. This was supported by a participative process with local stakeholders, including the rice sector, irrigation communities and nature conservation NGOs. This served to establish the guidelines for a programme of adaptation and mitigation measures with a high consensus.
In terms of innovation, the project developed a new system of sediment recycling, promoted novel agronomic practices to reduce GHG emissions in the rice sector (i.e. AWD), produced new sediment transport guidelines for users and administrations, and a new sediment transport model for researchers. There has been interest from private companies, such as consulting and engineering companies, in exploring or incorporating the methods and techniques of sediment management in their business plans. There is good potential for this to lead to future research and development projects with the private sector and leading research groups.
Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).