RESUMO O Material Particulado (MP) está entre os principais contaminantes do ar. A Infraestrutura Verde (IV) vem sendo reconhecida como alternativa para melhorar a qualidade do ar. As árvores podem afetar diretamente os níveis de MP, interceptando partículas em sua superfície. Devido a essa capacidade, esta pesquisa teve como objetivo contribuir com informações sobre a viabilidade da vegetação verde para interceptar e identificar as principais fontes de poluentes atmosféricos. Amostras de cascas de árvores de parques urbanos de São Paulo (SP) foram utilizadas como monitor biológico de poluentes atmosféricos. Foi observado um decaimento exponencial das concentrações e aprisionamento de poluentes em direção à região mais interna dos parques. Além disso, foi possível distinguir a emissão de veículos leves das emissões de veículos pesados. O baixo custo do monitoramento e sua eficácia mostram que a IV ocupa papel de destaque na melhoria da saúde e a qualidade de vida das pessoas, bem como nas ações que buscam atenuar os efeitos da poluição do ar em cidades de médio e grande porte.

ABSTRACT Particulate Matter (PM) ranks among the main air contaminants. A Green Infrastructure (GI) has been recognized as an alternative to improve air quality. Trees can directly affect PM levels by trapping it on their surface. This study aimes to provide extra information on the feasibility of using green vegetation to trap pollution and also to identify the main sources of air pollutants in urban areas. Tree bark samples from urban parks in São Paulo, Brazil, were used as biological monitors of air pollutants. The trapping of pollutants and an exponential decay of their concentrations were observed towards the more inner sites of the parks. Furthermore, it was possible to discriminate light-duty from heavy-duty vehicle emissions. The low cost of monitoring and its effectiveness emphasize that a GI has a pivotal position in enhancing health and quality of life and in dealing with the effects of air pollution in medium-size and large cities.

Abstract Wavelength dispersive X-ray fluorescence spectrometry (WDXRF) is a suitable technique for the characterization of contaminated mining sites, providing a quick and reliable screening for areas of significant contamination. This study established and validated a non-destructive methodology for quantitative simultaneous determination of major and minor constituents in soil and sediments by WDXRF, which was further applied to quantify soil and sediment samples from Osamu Utsumi uranium mine (Caldas, Minas Gerais, Brazil). Elements such as Ce, La, Nd, Mn and U were found in more concentrated levels in the calcium diuranate deposit (DUCA), whereas Fe and Al were found at higher levels in the soil samples corresponding to sites where accentuated leaching processes have occurred. Comparatively, the levels of U and rare-earth elements were found in significantly higher levels in the sediments retrieved from the mine’s pit as a result of acid mine drainage. These findings are believed to be useful as an initial environmental assessment for the decommissioning process of the mine.