The marine ecosystem is also threatened by fires that hit wooded areas especially in summer: the combustion of biomass produces pollutants that end up contaminating the sediments of the seabed where benthic organisms at the base of the food chain live.
This is demonstrated by a mathematical-statistical study on the Mediterranean Sea, published in the journal Ecological Indicators by researchers from the University of Milan-Bicocca led by ecologist Sara Villa.
The experts reconstructed the spatial and temporal trend of the risk represented by the presence of 16 polycyclic aromatic hydrocarbons (PAHs) for benthic communities, the organisms that live in the sediments of the Mediterranean. Researchers also investigated the origins of PAH contamination in Mediterranean sediments.
The results indicate that these pollutants come mainly from anthropogenic sources due to incomplete combustion of coal, wood or gasoline or from industrial processes. However, they can also be emitted from natural sources such as forest fires or volcanic activity. Contaminants can be transported over long distances and can enter the aquatic environment through atmospheric paths after dry or wet deposition processes or be transported by rainwater to waterways and then to the sea. Other sources come from industrial processes such as the industrial use of petroleum and / or industrial or urban wastewater.
“We have found that as fires increase, contamination of marine sediments increases with a response time of approximately three years,” explains Villa. "This is a new and strategic aspect on which to hinge the fight against fires in wooded areas and push for greater public awareness, to protect not only the terrestrial environment but also the marine one".