Biomonitoring of emissions from an oil refinery in Cubatão, SP, with Psidium guajava 'Paluma': photosynthesis, growth and visible foliar symptoms

Abstract

The Atlantic Forest located in the Serra do Mar in Cubatão, São Paulo, is affected by several pollutants such as sulfur oxides, nitrogen oxides and particulate materials with varied composition. These pollutants are emitted by various industries, among them, Presidente Bernardes Refinery, that gets energy from burning oil. This model is being replaced by a more modern technology, which should result in the production of cleaner energy, therefore, is expected to reduce levels of air pollution in the vicinity of the refinery, mainly sulfur dioxide (SO2), pollutants that currently cause the greatest impact on the surrounding vegetation. The burning of natural gas, on the other hand, may increase the emission of volatile organic compounds, which are precursors of ozone (O3). Today, the concentrations of O3 in the region are not high; to see if they will not improve phytotoxic levels will be implemented a biomonitoring project during the trading system to generate energy. Saplings of Psidium guajava 'Paluma', a tree species sensitive to O3 that occurs in this region of Atlantic forest, will be used to evaluate possible changes in air quality. They will be exposed during the period of one year in six experimental sites distributed around the refinery (at three different altitudes on the road Caminho do Mar, which is behind the refinery and receive the winds that pass through it, one in the center of Cubatão, one next to the refinery at sea level, and one in an area under the wind, an area more protected from pollution in the valley of Pilões River), before and after the change of the process of obtaining energy. In this study, in which the plants will be directly exposed to the environment surrounding the refinery will be held also a semi-controlled experiment, in which the plants are kept in open-top chambers, and a number of them will be ventilated with ambient air and other with filtered air, therefore, with low concentrations of pollutants. All plants will be assessed on photosynthesis, growth and expression of visible foliar symptoms in order to evaluate possible changes in their responses to local air pollution. (AU)