Avaliação dos efeitos causados pela deposição ácida e de ferro particulado sobre processos fisiológicos e reprodutivos em espécies de restinga

• Autor(a) principal: Oliveira, Cláudio Roberto Meira de
• Data de Publicação: 2009
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/355
• topic: Restinga; Material particulado de ferro; Deposição ácida; Poluição ambiental; Fenologia reprodutiva; Restinga; Iron particulate matter; Acid deposition; Environmental pollution; Reproductive phenology; CNPQ::CIENCIAS BIOLOGICAS::BOTANICA

The Mata Atlântica bioma includes different ecosystems. Between them the Restinga ecosystem is the less studied. It is continuously exposed to the effects of the acid deposition and iron solid particulate matter (SPMFe) released by the activity of iron ore mining industries in the coast of the Espírito Santo state in Brazil. The present study was carried out in Restinga area (exposed and not exposed to the industrial emissions) and in semi-controlled environment. Physiologicals and ecologicals parameters were evaluated. In the Restinga area six plant species were studied: Lantana tiliaefolia, Cordia curassavica, silky Byrsonima, Psidium guajava, Anacardium occidentale and Schinus terebinthifolius. The species monitored in the polluted area showed higher iron content into the leaves. This high iron concentration promoted the development of toxicity and thus the appearance of injuries. The flowers formation and fruits production was reduced in the area exposed to the SPMFe and acid deposition. The most sensitive species was A. occidentale and P. guajava. The germination and emergence of plantlets was limited by the SPMFe deposition principally with the increasing of SPMFe deposited. The association of SPMFe with the acidity also caused reductions in the emergence of the plantlets possibly due the chemical and physical effects of its components. The simulated deposition of SPMFe on the soil and on the leaves of L. tiliaefolia, C. curassavica and S. terebinthifolius caused the appearance of injuries, reduction in the content of pigments, and change negatively the reproductive phenology of these species. Moreover, was reported reduction in photosynthesis and increased iron content in the leaves. An experiment was performed with the same plant species growing in Hoagland & Arnon nutrient solution with half ionic strength and pH 5. The results showed that the species presented different degrees of sensibility to the toxic effects of Fe-EDTA. The tolerance level decrease in the following order: S. terebinthifolius> C. curassavica> L. tiliaefolia. In reverse order, was observed a significant iron accumulation in the roots and leaves of L. tiliaefolia twice bigger than the values found in S. terebinthifolius, in spite of the reductions in photosynthetic rate in these species. In general, the flowers and fruits production was reduced in plants exposed to the Fe-EDTA treatment. The results showed that the emissions released from iron mining activities can affect the Restinga vegetation in different levels. In long term it can cause a decline in quantity and diversity of the most sensitive species.