Environmental Pollution 85 (1994) 109-116 PLANTS AS BIOINDICATORS OF AIR POLLUTION AT THE SERRA DO MAR NEAR THE INDUSTRIAL COMPLEX OF CUBATAO, BRAZIL Andreas Klumpp,* Gabriele Klumpp* Institut ffir Angewandte Botanik, Universitat Essen, Universitgitsstr. 5, D 45117 Essen. Germany & Marisa Domingos Instituto de Botdnica, Caixa Postal 4005, 01061-970 S6o Paulo. SP, Brazil (Received 13 November 1992; accepted 26 April 1993) Abstract As a result of air pollutant emisstons from the industrial complex of Cubatdo, Brazil, the Atlantic Forest vegeta- tion of the Serra do Mar shows severe and widespread damage. In order to obtain information on the type, intensiO, and causes of the vegetation damage, bioindicator plants were exposed at different distances from the emission sources. Air-pollution-induced effects were evaluated by estimation of visible inju o, symptoms and chemical analyses of leaves. The results prove the occurrence of phytotoxic levels of photochemical oxidants in wide parts of the research area. Intense fluoride-induced damage and high leaf fluoride concentrations were found in a valley downwind of fertiliser industries. The stud), showed that some of the traditional standardised bioindication methods fi'om temperate climates may be successfidly employed in biomonitoring programmes in trop#al and subtropical regions. INTRODUCTION In the estuaries of Cubat~o (in the State of S~.o Paulo, Brazil), one of the most important industrial complexes of South America was constructed, including fertiliser industries, steel works, refineries, chemical and petro- chemical plants. The industrial pool is situated at the foot of the coastal mountains, the Serra do Mar. The climate of the region is characterised by high annual precipitation of up to 4000 mm, high relative humidity and average temperatures of 20-25°C. The slopes of the mountains, which reach altitudes of 900 m and more above sea-level, are covered by the Atlantic Rain Forest (Mata Atlfintica), an ecosystem with a large species diversity, which has been severely threatened by * Present address: Instituto de Bot~.nica, Caixa Postal 4005, 01061-970 Sfi.o Paulo. SP, Brazil. Environ. Pollut. 0269-7491/94/$07.00 © 1994 Elsevier Science Limited, England. Printed in Great Britain 109 various human activities (Coutinho, 1962; Bigarella, 1991; Joly et al., 1991). At Cubatfio, during day-time, sea-land breezes are transporting the air pollutants emitted by the industrial stacks into the narrow valleys downwind, especially into the Mogi Valley, causing severe damage to vegeta- tion and soil of the Mata Atl~ntica ecosystem. As a consequence, trees of the upper tree layer show intense injury and a high mortality rate, leading not only to a reduction of species variety, but also to disturbances in the ecological capacity of maintaining water household and soil stability. The pollution-induced problems culminated in 1985 when, after heavy rainfalls, hundreds of mudslides occurred threatening population as well as industrial installations. Concurrently to reductions of pollutant emission and replantation of affected areas (SMA, 1990), an interdisciplinary research project, involving various German and Brazilian research institutes, was initiated in order to study dispersion, transformation and deposition of air pollutants in the Cubat~o region and the direct and indirect effects on soil and vegetation. As part of this project, it is intended to get an insight into the spatial and temporal distribution of gaseous air pollutants by the use of indicator plants. Whereas in temperate climates, especially in Europe and North America, active monitoring with bioindicators is a widely used means to monitor air quality (Manning & Feder, 1980: Arndt et al., 1987), only few data exist about such studies performed in subtropical and tropical regions. In Israel, for example, lichens and higher plant species were exposed near industrial areas in order to detect the accumulation of heavy metals in plant material and to assess the impact of gaseous air pollutants, respectively (Naveh et al., 1979; Garty, 1987). Several indicator species have been used to map the extent of air pollution by photochemical oxidants in Mexico (de Bauer & Krupa, 1990; Gonz61ez & Rivas, 1992). In Brazil, studies have been performed on the suitability of