FO3X – Ozone FACE

FO3X is an innovative FACE (Free-Air Controlled Exposure) installation that enables the study of the effects of ozone (O₃) on vegetation under real environmental conditions.

Unlike studies in the laboratory or in closed chambers, FO3X makes it possible to assess plant physiological activity and model stomatal flux. Consisting of three separate structures, each with the ability to modulate O₃ concentration, the system uses a network of Teflon tubes with microholes to emit a mixture of air and O₃, achieving desired concentrations.

It is a unique facility in Mediterranean Europe and is an integral part of the European research infrastructure AnaEE (Ecosystem Analysis and Experimentation) and registered under the ITINERIS (Italian Integrated Environmental Research Infrastructures System) project.

FO3X consists of a network of vertical tubes that diffuses ozone in an area of 50 m³ to simulate three conditions: fumigation with ambient air (control: C), fumigation of ozone at intermediate concentration (T1) and fumigation of ozone at high concentration (T2).

Three miniponds (artificial ponds with a diameter of 80 cm and volume of 200 liters each) were set up in the infrastructure, one for each control/treatment. A natural substrate (pebbles, sand and silt) taken from Pozza dei Cavalieri (Sesto Fiorentino) was placed in each minipond. The miniponds were filled with 175 liters of dechlorinated tap water. The following native aquatic plants were inserted: Menyanthes trifoliata (emerged plant, creeping), Myriophyllum spicatum (perennial plant, oxygenating), Nymphaea ibrida bianca. Ozone fumigation occurs every year from June through October. The miniponds are equipped with sensors that monitor temperature and electrical conductivity continuously at 4-hour intervals.

Since 2015, FO3X has hosted national and international researchers, studying 29 plant species and producing 46 scientific publications.