Morphophysiological changes in Psidium cattleianum caused by air emissions from a mining industry in Brumado, Bahia, Brazil

Abstract

Psidium cattleianum is a bioindicator species of air pollutants, notably NOx and SO2. The aim of this study was to evaluate the effects of air emissions from a mining industry in Brumado, Bahia, Brazil, on the morphophysiological characteristics of P. cattleianum. A field experiment was carried out with potted plants in two distinct areas: (1) permanent exposure to NOx and SO2 emissions; and (2) free from the influence of the plume formed by these air pollutants (control). Plant height, leaves area and quantity, leaves, stem and roots dry mass, and chlorophyll and soluble sugar contents were evaluated. In the plants exposed to the pollutant plume, height growth inhibition and leaf size and quantity reduction were observed, besides showing symptoms of chlorosis and necrosis. Dry matter production was also lower in all organs. The chlorophyll a content was lower, but chlorophyll b content did not change. The soluble sugars content was not affected by the pollutants. It was concluded that the atmospheric emissions from the mining industry negatively affect the physiological characteristics of P. cattleianum, inhibiting the plant growth.