Neste trabalho, avaliou-se a disponibilidade de nutrientes minerais e elementos tóxicos em cafés produzidos pelas agriculturas orgânica, tradicional e tecnológica no sudoeste da Bahia, Brasil. Os nutrientes minerais foram determinados em amostras de solos e tecidos de café por espectrometria de absorção atômica com chama (FAAS) e os elementos tóxicos (Cr, Ni, Cd e Pb) por espectrometria de emissão ótica por plasma indutivamente acoplado (ICP OES). A aplicação de métodos estatísticos (análises de agrupamento e de componentes principais) aos resultados analíticos confirmou a importância do "período de conversão", durante o processo de mudança do manejo da cafeicultura tradicional para orgânica. Os resultados possibilitam inferir que o Cd, Cu, Zn e outros elementos tóxicos contidos nos fertilizantes inorgânicos (utilizados na cafeicultura tradicional e tecnológica), e os níveis relativamente elevados de Cu e Zn presentes nos adubos orgânicos (utilizados na cafeicultura orgânica) podem causar aumentos dos níveis desses elementos nos solos agrícolas, podendo assim, passar para a cadeia alimentar através dos cultivos.The aim of this study was to evaluate of availability of nutrients and toxic elements in green coffees produced in traditional, technological and transitional organic farms in Southwest BahiaBrazil. Levels of the nutrients minerals were determined directly in samples of soils and coffee tissues from four farms by flame atomic absorption spectrometry (FAAS) and toxic elements (Cr, Ni, Cd and Pb) by inductively coupled plasma optical emission spectrometry (ICP OES). The application of statistical methods (cluster and principal components analysis) revealed the importance of the conversion period to guarantee a product genuinely organic during the change to organic agriculture. On the other hand, the study of correlations between agricultural methods and metals concentrations in coffee suggested that Cd, Cu, Zn and other toxic elements contained in some inorganic fertilizers used in the traditional and technological coffee farms may cause an increase of toxic metals concentration in the crop soil, be taken up by plants, and passed on in the food chain.
Available metals in soil Nutrients and toxic elements a b s t r a c tThe aim of this study was to evaluate the presence of nutrients and toxic elements in coffees cultivated during the process of conversion, on organic agriculture, in southwest Bahia, Brazil. Levels of the nutrients and toxic elements were determined in samples of soils and coffee tissues from two transitional organic farms by atomic absorption spectrometry (FAAS). The metals in soil samples were extracted by Mehlich1 and USEPA-3050 procedures. Coffee samples from both farms presented relatively high levels of Cd, Zn and Cu (0.75, 45.4 and 14.9 lg g À1 , respectively), but were still below the limits specified by the Brazilian Food Legislation. The application of statistical methods showed that this finding can be attributed to the addition of high amounts of organic matter during the flowering tree period which can act on the bioavailability of metal ions in soils.
Many studies have been carried out on the environmental impact of the research stations on the Antarctic continent. However, the assessment of indoor air quality in these confined environments has been neglected. The main objectives of this study are to investigate the granulometric distribution of the indoor particles in the different compartments of the Brazilian Antarctic Station, to examine the number and mass concentration of the indoor particles, to conduct chemical and morphological analyses of the indoor PM2.5, and to identify the possible sources of the PM. The results showed that Na, K, Cl, Fe, Zn, S and Si were the main elements detected. High levels of black carbon were recorded in the workshop, which may be associated with the use of diesel vehicles. To identify the human activities related to the indoor particle emission in the station, the size distribution of the particles in the living room was monitored for seven consecutive days, during normal station operation. It was possible to identify the influence of individual processes, such as incineration, cooking and the movement of people, upon the particle size number concentration. The indoor/outdoor (I/O) ratio for the total suspended particles (TSP), PM10, PM2.5 and PM1 measured was significantly larger than those reported for urban buildings. In general, the I/O ratio distribution for all the compartments shows peak values between 2.5 and 10 μm, which is often related to human activity, such as cleaning, personnel circulation or clothing surfaces. The maximum I/O ratio at this range varied from 12 to 60. In addition, the compartments affected by combustion processes tend to present a significant number of submicron particles.
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