Abstract This study was conducted to assess the physicochemical characteristics of urban forest soil contaminated by copper and the dynamics of macro- and micronutrients uptake by Schinus terebinthifolia and Eugenia uniflora seedlings. The seedlings received 0 (control), 60, 120, 180 or 240 mg Cu kg-1 soil applied to urban forest soil within São Paulo City, Brazil. Our results showed that K was reduced in Cu-contaminated soil used for S. terebinthifolia cultivation and that organic matter was higher in Cu- contaminated soil used for E. uniflora cultivation. Other physicochemical properties of soil remained unaltered. S. terebinthifolia presented nutritional imbalances in N, K and Mg on leaves, while E. uniflora presented nutritional imbalances in K on leaves and in S on roots. It can be concluded that copper contamination can negatively affect chemical and nutritional characteristics of urban forest soil, as well as the nutritional dynamics of S. terebinthifolia and E. uniflora.

ABSTRACT This study aimed to evaluate the accumulation and distribution of copper (Cu) in the pioneer tree Schinus terebinthifolius R. (aroeira) and non-pioneer tree Eugenia uniflora L. (pitanga) submitted to different concentrations of copper. The plants received 40 mL of Hoagland & Arnon (1950) n. 1 nutrient solution modified with 0.00032, 0.0032, 0.032 and 0.32 mM Cu2+ applied to the soil. We analyzed biomass, biometry and Cu contents in plants and the concentration of Cu in soil. Cu concentration in the soil contaminated with 0.32 mM Cu2+ was higher than other treatments. Neither species showed characteristics of plant phytotoxicity. However, the two species did exhibit different physiological responses to Cu; S. terebinthifolius accumulated the metal only in roots, while E. uniflora accumulated Cu in roots and leaves. The highest Cu concentration in soil was observed in the treatment with 0.32 mM Cu2+. Outstanding to foliar accumulation, E. uniflora could be used for biomonitoring.

O estudo objetivou verificar se a intensidade e precocidade de respostas foliares de curto prazo de Nicotiana tabacum 'Bel-W3' dependem dos níveis atmosféricos de ozônio e/ou das condições meteorológicas diárias em um Parque Estadual localizado na cidade de São Paulo, SE-Brasil. Entre 16 de setembro e 14 de outubro de 2002, três lotes contendo seis plantas envasadas foram expostos no ambiente por quinze dias. Necroses foliares, concentrações atmosféricas de ozônio e parâmetros meteorológicos foram medidos diariamente. A porcentagem média de área foliar com necroses variou de 5% a 20%. Um modelo polinomial de quarto grau foi proposto para explicar o progresso diário das necroses foliares nas plantas. Os níveis médios de ozônio aumentaram a partir da manhã (1.3-39.2 ppbv) até o meio dia (1.6-52.0 ppbv), diminuindo a tarde (0.5-39.9 ppbv). O padrão diário de aumento de área foliar com necroses não foi relacionado estritamente com ozônio, mas foi influenciado pelas condições meteorológicas e pelo estágio de desenvolvimento das folhas.

The present study aimed to study if the intensity and precocity of short-term leaf responses of Nicotiana tabacum 'Bel-W3' depended on the daily atmospheric levels of ozone and/or daily meteorological conditions in a State Park located in the city of São Paulo, SE Brazil. From 16 September to 14 October 2002, three lots of six potted plants were exposed for fourteen days. Leaf necrosis, atmospheric ozone concentrations and meteorological parameters were daily measured. The average percentage of leaf necrosis ranged from 5% to 20%. A 4th degree polynomial model was proposed to explain daily progress of leaf necrosis on plants. The average ozone levels were increased from morning (1.3-39.2 ppbv) to the midday (1.6-52.0 ppbv) and decreased in the evening (0.5-39.9 ppbv). Daily pattern of accumulated percentage of leaf necrosis was not strictly related to ozone, but was influenced by the meteorological conditions and stage of development of leaves.

Psidium guajava 'Paluma' é sensível ao ozônio, ao qual responde com características injúrias foliares visíveis. Foram avaliadas a concentração de ácido ascórbico (AA) e a atividade das enzimas superóxido dismutase (SOD) e peroxidases (POD) em folhas novas e velhas de plantas expostas (n = 13) em região contaminada por ozônio (Ibirapuera, São Paulo, SP) e em um ambiente controlado (casa de vegetação com ar filtrado), com o objetivo de avaliar a ocorrência de injúrias latentes (alteração em AA, SOD e/ou POD) e se a ocorrência destas diferia entre folhas com ou sem injúrias visíveis. A concentração de AA foi maior nas plantas do Ibirapuera, sem diferença entre novas ou velhas e com ou sem injúrias. A atividade de SOD e POD diferiu entre folhas novas e velhas, mas não com relação ao local de exposição e a presença ou ausência de injúrias foliares. Não houve decréscimo na biomassa das plantas expostas no Ibirapuera. Conclui-se que em P guajava 'Paluma' SOD e POD não estão relacionadas à proteção contra injúrias foliares visíveis nessa espécie e que o AA é um indicador de injúria latente.

Psidium guajava 'Paluma' is sensitive to ozone, to which reacts with characteristic visible foliar injuries. The concentration of ascorbic acid (AA) and the activity of enzymes superoxide dismutase (SOD) and peroxidase (POD) had been evaluated in new and old leaves of plants exposed (n = 13) to ozone in a contaminated area (Ibirapuera, São Paulo, SP) and in a controlled environment (glasshouse with filtered air) to assess the occurrence of latent injuries (alteration in AA, SOD and/or POD) and if the occurrence of these differed between leaves with or without visible injuries. The AA concentration was higher in plants of Ibirapuera, without difference between new or old and with or without visible injuries. The activity of SOD and POD differed between new and old leaves, but not with relation to the site of exposition and the presence or absence of foliar injuries. There was no significant decrease in biomass in plants exposed in Ibirapuera. We conclude that in P. guajava 'Paluma' SOD and POD are not related to the protection against visible foliar injuries and that the AA is a indicator of latent injury.

Muitos estudos situam a germinação das sementes dentre os estágios de desenvolvimento extremamente vulneráveis às condições ambientais e que a resposta germinativa à acidez pode auxiliar o conhecimento sobre diferenças na composição florística. Sementes de duas espécies nativas (Erythrina speciosa Andr. e Eugenia brasiliensis Lam.) e uma cultivada (Cucumis sativus L.) foram avaliadas quanto à germinação em diferentes níveis de acidez e a concentrações de alumínio, esta relacionada indiretamente com o pH do solo. Sementes de E. speciosa e C. sativus germinaram inclusive em pH 1,0. O alumínio afetou a germinação das três espécies, com inibição em pH 1,0 e 2,0. Constatou-se que as sementes de E. brasiliensis apresentaram a maior suceptibilidade às condições químicas do meio. Os resultados demonstraram que o efeito da acidez sobre a germinação provavelmente ocorre entre a fase de embebição e a fase da protrusão da radícula.

Many studies have described seed germination as an extremally vulnerable growth phase and seed germinability in response to acidity may subsides the knowledge about the differences in floristic composition. Seeds of two native species from Brazil, Erythrina speciosa Andr. and Eugenia brasiliensis Lam., and a cultivated species (Cucumis sativus L.) were evaluated in relation to their sensibility to acidity and to different aluminium concentration, variable indirect related with the pH of the soil. Seeds of E. speciosa and C. sativus did not loose germinability even in pH 1.0. Aluminium affectted the germinability of the three species, resulting in total inhibition of germination in pH 1.0 and 2.0. E. brasiliensis showed the greatest sensitivity to environmental chemical conditions. Results showed that the effects of acidity on germination probably affect the phase of the germination process between imbibition and radicle protrusion.