That is the main finding of the ‘Dourozone’ project, as it has been dubbed, which assessed for the first time the effect of the exposure of Douro vines to ozone, both in the current climate and in climate-change scenarios.

Monitoring of the vines carried out in the course of the project confirmed that exposure to current ozone levels could cause damage to the vine.

In the present climate, the results of ozone modeling, as well as the values measured during the experiment, indicate that the region’s high ozone levels may lead to an average productivity loss of around 30%, if exposure to the values recorded take place on a recurring basis for three consecutive years.

The study also analysed the effects of ozone in future climate scenarios, concluding that there will be an increase in water stress for the vines and a decrease in quality due to the reduction in precipitation and warmer nights.

Researchers state that the effects of ozone on Douro vines in a climate-change scenario could be somewhat less if there is a significant reduction in gas emissions.

However, they highlight the fact that the accumulated exposure amounts will continue to exceed the ideal value for the protection of vegetation, as established by the European Union’s air quality framework directive.

The ‘Dourozone’ project, which concluded in June, was undertaken by the Centre for Environmental Studies of the Sea (CESAM), an associate laboratory of Aveiro University, and coordinated by the latter’s Department of Environment and Planning and with the participation of its Department of Physics, in partnership with Bragança the Polytechnic Institute.

Researchers hope to be able to continue their work and collaboration, and are already pondering other studies on vineyards in Portugal.