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In both Brazilian and European regulations, the impact assessment of sewage discharges into coastal waters is based on microbiological analyses of fecal indicators such as Escherichia coli, frequently used in prevision hydrodynamic models. However, the decay rates of E. coli vary depending on environmental conditions, and analysis may lead to inaccurate conclusions. This study aimed to analyze the decay of culturable and viable (but not culturable) E. coli in outdoor conditions, by creating microcosms inoculated with pre-treated sewage. The microcosms were filled with 9.88 L of filtered water (0.22 μm membrane), 3.5% salt, 0.1-0.2% BHI, and 1% bacterial suspension obtained by reverse filtration. PMA-qPCR of E. coli uidA gene and Colilert measurements were applied to evaluate population counts after 2 h, 4 h, and 26 h. After nine hours of exposure to solar radiation, the viable cells decreased to 2.76% (interpolated value) of the initial population, and the cultivable fraction of the viable population accounted for 0.50%. In the dark period, the bacteria grew again, and viable cells reached 8.54%, while cultivable cells grew to 48.14% of initial population. This behavior is possibly due to the use of nutrients recycled from dead cells. Likewise, populations of E. coli in sewage outfalls remain viable in the sediments, where resuspension can renew blooming.

Obtaining uncultured Escherichia coli from natural waters is an important step in the study of microbes in the environment, which are critical for bacterial decay and microbial source tracking. The quality of the samples used can influence the assays, because high contaminant concentrations, differing cell ages, and physiologic states can impair results. The proposed separation is based on a three-step filtration method applied to replicates of seven samples from a sewage plant affluent, collected in different periods. Aliquots of the leachate were inoculated into microcosms, aiming to observe the cultivability of the cells. The assay resulted in colimetry values ranging between 104 and 105 cells. In the leachate, averages of 1.05% of total coliforms and 1.10% of Escherichia coli were recovered from original samples. Although enduring unfavorable temperatures, salinities, and nutritional conditions, the inoculated microcosm populations grew approximately 310 times after 24 h. The final leachate contained cultivable cells in appropriate physiological states and quantities for inoculum in microcosm sets. The bacteria obtained from the leachate were also appropriate for surveys of microbial source tracking, because, in the developed procedure, organisms were separated from contaminants, while cell concentrations were sufficient for inocula. Made available in DSpace on 2020-12-08T09:04:20Z (GMT). No. of bitstreams: 1 Separation-of-Escherichia-coli-from-natural-samples-2020.pdf: 483657 bytes, checksum: f8d6cb67fb8f10346d404517e996bb2b (MD5) Previous issue date: 2020

Landfill leachate is a potential environmental pollutant. Physicochemical analyses allow identifying its elements while the use of ecotoxicological tests aims to understand the relation with the environment. The germination assay of Senna macranthera in different substrates (filter paper, commercial-SCM, conventional-SCV and organic-SOR) was performed with different doses of leachate. The objective was to identify the potential impact of leachate by determining the concentration able to cause inhibition in 50% of the seeds (LC50) and the values of the no observable effect concentration (NOEC) and the lowest observed effect concentration (LOEC). The LC50 and LOEC occurred in the treatments with 6.25 while NOEC was with 3.125%. The test in substrates, It was not possible to identify the LC50 in the SCM. For the SCV was with 66 and in SOR with 25%. The NOEC and LOEC for SCM and SCV were 25 and 50% and in SOR with 50 and 100%.

Quando lançado diretamente no solo, o óleo vegetal residual (OVR) ocupa os espaços que naturalmente seriam ocupados pela água e pelo ar, provocando a sua impermeabilização. Adicionalmente, a fauna e a flora deste local ficam impedidas de absorver os nutrientes, bem como as sementes não conseguem germinar o que torna o solo impróprio para o cultivo. Dependendo das características físico-químicas do solo e outras características como relevo e regime pluviométrico, o OVR pode migrar deste e atingir corpos hídricos e até mesmo o lençol freático. O presente trabalho avaliou os impactos associados ao descarte inadequado do OVR em propriedades físico-químicas de dois solos com texturas distintas (um arenoso e outro argiloso) em colunas de lixiviação. Os resultados mostram que o tratamento com 20 mL de OVR em solo arenoso, provocou maior impacto em 50% dos parâmetros analisados. O tratamento com 26 mL do OVR, em solo argiloso, provocou maior impacto em 67% dos parâmetros analisados. Portanto, o OVR mostrou-se como um resíduo de potencial contaminante se for disposto indevidamente sobre os dois tipos de solo, o que pode provocar impactos negativos não só no solo, mas também nas plantas cultivadas e na água subterrânea

As fatalidades derivadas da fome podem superar as mortes em uma guerraconvencional. Por isso, a alimentação de uma nação deveria ser consideradacomo assunto da Segurança Nacional. No entanto, o conceito de SegurançaNacional só evoluiu nessa direção com o fim da Guerra Fria e com a percepçãopública de que as Mudanças Globais poderiam exacerbar tensões relacionadasà escassez de alimentos e água. Nesse sentido, o presente trabalho apresentauma evolução conceitual da questão alimentar dentro do contexto da SegurançaNacional. A situação do Brasil é contrastada para cenários internacionaisdescritos em literatura na tentativa de ganhar maior atenção do Ministério deDefesa em relação a agricultura brasileira, devido ao seu importante papel nascinco expressões do poder nacional.

Death from hunger in the world may overcome the number of deaths in conventionalwar. Therefore, food should be considered a National Security core issue of anycountry. However, the concept of National Security has evolved in this directiononly with the end of the Cold War and a growing public awareness that globalchanges may exacerbate tensions related to food and water shortages. Accordingly,this paper presents a conceptual evolution of the food issue within the context ofNational Security. Brazil’s situation is contrasted to international scenarios outlinedin an attempt to earn greater attention from the Ministry of Defense regardingBrazilian agriculture due to its important role in the five expressions of nationalpower.

Series describing the evolution of patients with severe acute respiratory distress syndrome (ARDS) secondary to COVID-19 and supported with extracorporeal membrane oxygenation (ECMO) during the first wave of the pandemic have reported mortalities ranging from 30 to 60% [1, 2]. More recent publications have demonstrated a trend towards a higher mortality in COVID-19 patients receiving support in later periods of the pandemic, even though the overall mortality of the disease seems lower [3, 4]. The reasons for this difference are not clear. Statistical analysis was carried out in the Statistics and Bioinformatics Unit (UEB) Vall d'Hebron Hospital Research Institute (VHIR). The following practitioners provided care for the study patients

A avaliação das medidas de proteção e de remediação em áreas rurais contaminadas por um acidente nuclear é mais complexa do que para as áreas urbanas, devido à forte influência de grande número de parâmetros e variáveis associadas a clima, dieta, hábitos alimentares, práticas agropecuárias e tipo do solo da área. Assim, não é possível realizar estudos gerais aplicáveis a qualquer tipo de área. Estudos específicos devem ser feitos nas áreas com maior probabilidade de serem contaminadas devido a um acidente nuclear. No caso da Central Nuclear brasileira em Angra dos Reis, a priorização destas áreas foi baseada em aspectos radiológicos e econômicos. Este estudo preliminar demonstrou que as diferenças nas doses de ingestão devido a diferentes tipos de solo no Brasil são mais relevantes do que as diferenças regionais nas dietas. O produto mais relevante para a dose no público foi identificado como sendo o leite. A contribuição da ingestão de leite para a dose total depende da época do ano quando o acidente ocorre. O momento de aplicação da medida de proteção tem um efeito importante na redução percentual da dose que pode ser alcançada. Em particular, para o I- 131, as medidas de proteção relacionadas com a ingestão de leite devem ser consideradas dentro da fase de emergência a fim de serem eficientes. Made available in DSpace on 2019-11-11T18:13:43Z (GMT). No. of bitstreams: 1 Estudopreliminarparaaremediacaodeareasruraisaposumacidentenuclearouradiologico2019.pdf: 1065640 bytes, checksum: 12ab79272d4716233baede28565b1d49 (MD5) Previous issue date: 2019

Currently, water scarcity, especially in irrigated agriculture, has led researchers to study reuse to study industrial and sewage reuse. Landfill leachates deserve special attention due to its difficulty of tratment they are effluents that are difficult to treat and because it contains essential susbstances for plant nutrition, such as nitrogen, phosphorus and potassium and its application in agriculture can be considered a noble use if it is properly handled and does not cause phytotoxicity. This study investigated the effects of different dilutions of treated and non-treated landfill leachate on germination and vitality of sunflower seed (cv. BRS 321), its effects in growth,and vitality and soil atributes under sunflower culture in greenhouse. The leachate was treated by two electro-Fenton process or distillation. The results showed that sunflower cv. BRS 321 seeds, germinated vigorously up to 25% effluent dilution, showing resistance to salinity and phytotoxicity at 50% raw leachate dilution. 15% dillution showed satisfactory results in sunflower growth and nutrition. However the leachate use of higher concentrations showed some changes in soil characteristics. This study suggests that landfill leachate can be used in seed germination under proper use and application, in their lowest leachate concentrations and always based on the chemical analyzes of the leachate.

Os movimentos de massa são feições naturais do Ambiente de Mata Atlântica, trazendo diversas transformações na paisagem, tanto do ponto de vista ecológico como hidrológico. O presente trabalho observou como se dá a recuperação dos nutrientes do solo e da fauna de microartrópodes em três áreas de deslizamento, levando em conta as características morfológicas de cada uma, que variam em tamanho e forma, sempre as comparando com uma área de floresta clímax local. Observou-se que as clareiras de maior porte apresentam condições menos favoráveis a sucessão, assim como maior propagação de efeito de borda. A densidade da fauna diferiu sensivelmente entre as áreas de clareira e a da floresta, assim como os principais nutrientes do solo, com maiores teores na floresta e no topo do solo, principalmente o fósforo. A diversidade de habitats que são criados por estas clareiras pode estar fortemente associada à biodiversidade elevada típica destes ecossistemas, influenciando diretamente na sua dinâmica na resiliência deste.

In the environmental science and engineering community, nanohydroxyapatite (nHAp) has been widely applied for the remediation of contaminated soil and purification of wastewaters polluted with heavy metals for its strong ability to fix these contaminants. Based on this process, the aim of the present study was to evaluate the impact of nHAp in sorption/desorption of Cu, Zn, Fe and Mn in microcosm experiments, considering different environmental conditions and investigating the effects of pH, contact time and influence of natural organic matter and contamination with Cu and Zn. Due to its relevance as a regional water supply source, the environmental scenario of Juturnaiba reservoir (Rio de Janeiro State, Brazil) was chosen as basis for the microcosm experiments. It was observed that nHAp had an effect on Zn and Cu behavior, acting as a captor and promoting the reduction of their dissolved concentration in the water treatment sludge after water contamination with these metals. However, this behavior was modified by the addition of humic acid and acid to the microcosm system. On the other hand, the behavior of Fe and Mn was impacted by these nanoparticles in an opposite way.

A fim de avaliar o efeito do extrativismo seletivo sobre o subsistema de decomposicao na Floresta Atlântica de Tabuleiros, foram estudadas as formas de humus numa area nuclear protegida (SOO) e em dois fragmentos representativos dos remanescentes florestais na escala da paisagem. Os estoques de materia orgânica sao menores em SOO Reserva que nos fragmentos onde a materia orgânica se acumula no horizonte A. A qualidade do folhico difere entre os sitios, com menores proporcoes de calcio e fosforo nos fragmentos; para os horizontes hemi-orgânicos, valores menores de Ca2+ e, inclusive, de bases de troca, pH e saturacao em bases (V%) foram igualmente registrados. As formas de humus foram classificadas como mull mesotrofico tropical para SOO Reserva e mull oligotrofico tropical para os fragmentos, nos quais a acumulacao de materia orgânica estaria relacionada ao oligotrofismo do solo e aos altos valores de Al3+ ligado a compostos orgânicos de dificil biodegradacao. O conjunto dos resultados sugere uma menor reciclagem de calcio e um menor "turnover" da materia orgânica nos fragmentos onde houve extrativismo que em SOO. Finalmente, nossos resultados mostram que nos humus analisados existe uma relacao estreita entre a qualidade do folhico e as caracteristicaspedologicas, que levam, nos fragmentos, a outra forma de funcionamento do subsistema de decomposicao, propria de estagios sucessionais secundarios. ABSTRACT - HUMUS FORMS IN TABLELAND ATLANTIC FOREST FRAGMENTS - ES, BRAZIL: EFFECTS OF SELECTIVE LOGGING ON DECOMPOSITION SUBSYSTEM In order to assess the effects of logging under the decomposition subsystem in Tableland Atlantic Forest hotspot we studied the humus-forms in a protected nuclear area (SOO) and in two fragments (PN and BIO) as a model of current remnants at the landscape level. Organic matter stocks were lower in SOO than in fragments where organic matter accumulated in the A horizon. Litter quality is markedly different across sites, with lower calcium and phosphorous proportions for fragments, as well as for hemorganic horizons, where minor values of Ca2+, exchangeable bases, pH and base saturation were also registered for fragments. Two humus forms were classified: a tropical mesotrophic mull in SOO Reserve and a tropical oligotrophic mull in fragments. Organic matter accumulation in fragments is likely to be related to poorer nutrient status and to higher Al3+ linking to less biodegrading organic compounds. These results suggest lower calcium recycling and a slow organic matter turnover into logging fragments compared to the protected Reserve. Finally, our results show that for the humus forms analyzed, there is a relationship between litter quality and soil characteristics, which leads to another way of functioning of the decomposition subsystem, characteristic of a secondary successional stage in the fragments.

A cidade de Santo Amaro da Purificacao (BA) foi contaminada por mais de 30 anos com escorias de uma fundicao de Pb. O objetivo deste estudo foi o de avaliar o grau de contaminacao por chumbo em solos coletados proximos a metalurgica, assim como avaliar a toxicidade proporcionada por chumbo nestes solos e identificar a distribuicao geoquimica do Pb nestes solos antes e apos o tratamento com diferentes fontes de fosforo. Os solos foram remediados com a aplicacao de KH2PO4 e rocha fosfatada. Apos 120 dias de experimento, os resultados confirmam a eficacia do sal KH2PO4 como atenuante da ecotoxicidade do Pb e a migracao deste metal de fracoes labeis para fracoes geoquimicas mais recalcitrantes do solo.

A liberacao de diversos tipos de nanoparticulas no ambiente aquatico pode resultar na exposicao direta ou indireta do homem e de organismos aquaticos, ou impactos no comportamento de metais. A ausencia de legislacao ambiental especifica para o descarte de rejeitos oriundos de atividades que utilizam nanoparticulas, como centros de pesquisa, servicos de medicina nuclear e a industria, tem contribuido para a liberacao descontrolada desses materiais no meio ambiente tornando-os relevantes dentro do contexto ecotoxicologico. Neste estudo, nanoparticulas (nanohidroxiapatita e acido D, L-lactico-co-glicolico - PLGA) com uso promissor pela medicina nuclear foram avaliadas por ensaios em microcosmos, reproduzindo-se as condicoes do Canal do Cunha (RJ), sistema aquatico costeiro, impactado por rejeitos industriais, domesticos e hospitalar, com elevados teores em metais e materiais orgânicos, ja reportados na literatura. Os resultados deste estudo nao identificaram impactos dos diferentes nanomateriais no comportamento de metais dissolvidos (Cu, Mn e Zn), na concentracao testada, provavelmente devido ao desenvolvimento de uma emulsao bacteriana nos microcosmos, que promoviam flutuacoes atipicas na concentracao dos metais dissolvidos, principalmente Cu e Zn. Estudos similares com nanomateriais em concentracoes superiores as testadas sao indicados para corpos d´agua em nivel avancado de degradacao qualitativa.

This study aims to evaluate the effects of oilfield water (OW), treated by a hybrid process of electrocoagulation and reverse osmosis (EC–RO), on seed germination and early growth characteristics of sunflower (Heliantus annus L.). In the EC step, tests were conducted with 28.6 A m−2 current density and 4 min. reaction time. In the RO step, the system was operated with 1 L min−1 constant flow and 2 MPa, 2.5 MPa and 3 MPa feed pressures. In all feed pressures, RO polymeric membranes achieved very high removals of chemical oxygen demand (up to 89%) and oils and greases (100%) from EC-treated effluent. In best feed pressure (2.5 MPa), turbidity, total dissolved salts, electrical conductivity, salinity, toxic ions and sodium adsorption ratio values attained internationally recognized standards for irrigation water. Using EC–RO (feed pressure:2.5 MPa) treated OW, germinated sunflower seeds percentage (86 ± 6%), speed of germination (30 ± 2) and biomass production (49 ± 5 mg) were statistically similar t...

The increasing concern regarding the preservation of soil quality suggests the adoption of quality reference values as a first step in environmental monitoring actions. In this context, the objective of this study was to establish soil quality reference values for Al, Zn, Mn, Cd, Fe, Pb, Ni, Cr, and Cu and to correlate several soil properties with the occurrence of these elements in the hillslope region of Rio de Janeiro State. Sixty-two samples were collected at depths of 0-20 and 20-40 cm and analyzed using the USEPA method 3051A. After clustering analysis, the samples were separated into three groups. Classification functions were obtained based on the variables pH - Mg - Fe - Mn, i.e., the variables that were best related to heavy metal content. We determined to establish the quality reference values for the 75th percentile of the three groups. The relief forms of the area, which facilitate the transport of soil fine-particle fractions and accumulation in lowlands, were revealed to be one of most important factors in understanding the distribution of soil heavy metals.

A first large-scale systematic survey of natural radioactivity contents of soils of the state of Rio de Janeiro is presented, focused on the establishment of Quality Reference Values (QRVs). Undisturbed soil samples were collected from 243 areas and analyzed by gamma spectrometry. The activity contents varied largely, ranging from 12.2 to 1,029 Bq kg-1 for 40K (geometric mean of 111.1 Bq kg-1), from 3.5 to 99.8 Bq kg-1 for 226Ra (geometric mean of 29.7 Bq kg-1), and from 5.4 to 314.5 Bq kg-1 for 228Ra (geometric mean of 67.1 Bq kg-1). The highest contents of radium isotopes were found in soils developed on igneous rocks (Leptosol), and the lowest in a soil of sedimentary origin (Podzol). Among the different soil types, the radioisotope contents differed substantially. Separate QRVs were calculated for each radionuclide by the 75th and 90th percentile approach, and the QRVs were estimated for each soil type. The results emphasized the restrictiveness of QRVs based on the 75th percentile or of a single overall QRV for all soils. Therefore, rather than estimating a separate QRV for each radionuclide for the State, we suggest the use of an upper threshold value, defined as the 90th percentile, and a specific QRV for each soil type area. Made available in DSpace on 2018-11-25T23:30:17Z (GMT). No. of bitstreams: 1 2018046.pdf: 776856 bytes, checksum: f1e3b26e1110cd386b46bbc7bd6fad1d (MD5) Previous issue date: 2018-11-21

A geração de lixiviado de aterro sanitário ocorre devido à degradação dos resíduos sólidos que apresenta-se como um líquido potencialmente poluidor que pode acometer os recursos naturais nas proximidades. A avaliação desse risco pode ser realizada por testes de ecotoxicidade via determinação da concentração letal (CL50). O objetivo deste estudo foi avaliar o impacto do lixiviado de aterro sanitário sobre organismos aquáticos, utilizando o Brachydanio rerio como organismo teste. Realizou-se um bioensaio do tipo estático, em aquário de vidro com volume total de 1,0 L; a água de preenchimento foi mantida sob temperatura em torno de 26 ± 2 ºC, sem cloração, pH 7,0 e OD 8 mg L-1. Cada aquário recebeu dez peixes com peso individual variando entre 80 e 100 mg, respeitando-se a densidade máxima de 1,0 g L-1. Utilizou-se o delineamento inteiramente casualizado, composto de 6 tratamentos com níveis crescentes de lixiviado de aterro (1,0, 1,8, 2,0, 2,5, 2,7 e 2,8%), diluídos em água deionizada, para o grupo teste e um grupo controle (água deionizada) ambos em triplicata. A CL50 de 2,35% de lixiviado reforça a necessidade do tratamento e/ou reuso como forma de minimizar os possíveis impactos ao meio, principalmente em organismos aquáticos. Made available in DSpace on 2019-02-26T00:39:40Z (GMT). No. of bitstreams: 1 2019010.pdf: 313070 bytes, checksum: 15028ec8044b72cc0dfbc3ec4421673d (MD5) Previous issue date: 2019-02-25

This study aims to evaluate possible toxic effects of oil and other contaminants from oilfield-produced water from oil exploration and production, on seed germination, and seedling development of sunflower (Helianthus annuus L.). In comparison, as treated by electroflocculation, oilfield-produced water, with lower oil and organic matter content, was also used. Electroflocculation treatment of oilfield-produced water achieved significant removals of chemical oxygen demand (COD) (94 %), oil and grease (OG) (96 %), color (97 %), and turbidity (99 %). Different OG, COD, and salt levels of untreated and treated oilfield-produced water did not influence germination process and seedling biomass production. Normal seedlings percentage and vigor tended to decrease more intensely in OG and COD levels, higher than 337.5 mg L(-1) and 1321 mg O2 L(-1), respectively, using untreated oilfield-produced water. These results indicate that this industrial effluent must be treated, in order to not affect adversely seedling development. This way, electroflocculation treatment appears as an interesting alternative to removing oil and soluble organic matter in excess from oilfield-produced water improving sunflower's seedling development and providing a friendly environmental destination for this wastewater, reducing its potential to harm water resources, soil, and biota.

O objetivo deste trabalho foi avaliar a possibilidade de antecipar a amostragem foliar em arroz de sequeiro, para viabilizar o diagnóstico nutricional em tempo hábil para intervenção. Foram coletadas 107 amostras foliares em ensaios de materiais genéticos da Embrapa Rondônia, no Estado de Rondônia, em três épocas de amostragem: antecipada, aos 30 e 40 dias após a semeadura (DAS); e padrão, aos 65 DAS. Foram obtidas as normas de diagnose da composição nutricional (CND) para cada época avaliada, as quais foram utilizadas para o diagnóstico em todas as épocas, tendo-se comparado os resultados do potencial de resposta à adubação sob duas ou três classes de suficiência nutricional, e verificado o grau de concordância entre os diagnósticos. O uso de duas classes de suficiência aumenta a possibilidade da antecipação da época de amostragem para diagnose foliar, o que viabilizaria o diagnóstico nutricional em tempo hábil para a correção ou a mitigação de eventuais deficiências nutricionais. A antecipação da diagnose foliar em arroz de sequeiro depende do desenvolvimento de normas de diagnose específicas para cada período amostral. The objective of this work was to evaluate the possibility of anticipation of foliar sampling in upland rice, in order to enable nutritional diagnosis for timely intervention. One hundred and seven leaf samples were collected from genotype trials of Embrapa Rondônia, in the state of Rondônia, Brazil, in three sampling times: anticipated, at 30 and 40 days after sowing (DAS); and standard, at 65 DAS. Composition nutrient diagnosis (CND) norms were obtained for each evaluated time and used for diagnosis on all evaluation times, comparing the results from the potential response to fertilization under two or three nutritional sufficiency classes, and checking the degree of agreement between the diagnostics. The use of two sufficiency classes increases the possibility of anticipating sampling time for foliar diagnosis, which would enable timely nutritional diagnosis to correct or mitigate eventual nutritional deficiencies. The anticipation of foliar diagnosis in upland rice depends on the development of specific nutritional diagnosis norms for each sampling time.

Located in the south-western part of Brazil, the state of Rio de Janeiro is geotectonically contained within a complex structural province that resulted in the amalgamation of the Western Gondwana Paleocontinent. To undertake an extensive radiological characterization of this complex geological province and investigate the influence of bedrock, soil type and soil chemical-physical characteristics on natural radionuclide levels in soils, 259 surface soil samples were collected that encompassed the main soil types and geological formations throughout the state. Gamma spectrometry analysis of the samples resulted in median values of 114 Bq.kg-1for 40K, 32 Bq.kg-1 for 226Ra and 74 Bq.kg-1 for 228Ra. The median value for 226Ra was similar to the world median value for soils, the 40K value was well below the worldwide value, and that for 228Ra exceeded the world median value. The intense weathering caused by the high rainfall rates and high temperatures may be responsible for the low levels of 40K in the soils, of which the strongly acidic and clayey soils are markedly K-depleted. A soil from a high-grade metamorphic rock (granulite) presented the lowest 226Ra (18 Bq.kg-1) content, whereas the highest levels for 226Ra (92 Bq.kg-1) and 228Ra (139 Bq.kg-1) were observed in a young soil enriched in primary minerals (Leptsol). A lowland soil (Gleysol) showed the highest median of 40K (301 Bq.kg-1). Strongly acidic soils tended to present high amounts of 226Ra, and sandy soils tended to contain low levels of 228Ra. The external radiation dose indicates that the state has a background radiation level within the natural range.

The objective of this work was to determine reference values for evaluating the nutritional status of 'Pêra' orange trees in different fruiting stages, using the compositional nutrient diagnosis (CND) method. The study used 243 leaf samples from 81 plots, with samplings performed in plants bearing fruits with three and six months of age, and also in the main harvest (nine months). Plots with productivity higher than 30 Mg ha-1 were selected for the establishment of reference standards. Three normal ranges were evaluated for each nutrient in the reference population, comprehended by the confidence interval (CI) of the foliar content averages, by the mean±standard deviation (±SD), and by the mean±⅔SD. Regardless of the normal range of nutrients used, the leaf sampling periods interfered with the nutritional status of 'Pêra' orange tree. The normal ranges obtained from the criteria CI and ±⅔SD of the nutrient contents observed in the reference population frequently provided similar nutritional diagnoses. Zn, Ca, and Fe are the elements that most often limit the production of 'Pêra' orange in the state of Amazonas, Brazil. Resumo: O objetivo deste trabalho foi determinar valores de referência para avaliação do estado nutricional de laranjeiras 'Pêra' em diferentes estádios de frutificação, com uso do método de diagnose da composição nutricional (CND). Foram utilizadas 243 amostras foliares, provenientes de 81 glebas, com coletas em plantas com frutos de três e seis meses de idade e, também, na colheita principal (nove meses). Glebas com produtividade superior a 30 Mg ha-1 foram selecionadas para o estabelecimento dos padrões de referência. Foram avaliadas três faixas normais para cada nutriente, na população de referência, abrangidas entre o intervalo de confiança (IC) das médias dos teores foliares, a média±desvio-padrão (±DP) e a média±⅔DP. Independentemente da faixa normal de nutrientes utilizada, a época de amostragem foliar interferiu no estado nutricional da laranjeira 'Pêra'. As faixas normais obtidas a partir dos critérios IC e ±⅔DP dos teores nutricionais observados na população de referência proporcionaram diagnósticos nutricionais frequentemente semelhantes. Zn, Ca e Fe são os elementos que mais frequentemente limitam a produção da laranja 'Pêra' no Amazonas.

Column and vessel experiments were conducted to investigate changes in mobility, leaching, and availability of lead (Pb) and cadmium (Cd) in contaminated soil (Santo Amaro Municipality, Bahia State, Brazil) after treatment with different sources of phosphate followed by assessment of phytoextraction by vetiver grass [Vetiveria zizanioides (L.)]. Columns were filled with contaminated soil and KH2PO4 (T1 treatment), reactive natural phosphate fertilizer (NRP) (T2 treatment), KH2PO4 mixed with NRP (T3 treatment), and untreated contaminated soil used as reference soil (T0 treatment). After 60 days, soil samples were collected from each column every 10 cm in depth and vessel experiments were initiated by planting vetiver grass. After 90 days, Pb and Cd were extracted from the soil and from the plant tissues using diethylenetriaminepentaacetic acid (DTPA) and nitro-peroxide extraction, respectively. Metal mobility was assessed using two methods: the toxicity characteristic leaching procedure (TCLP) and ...

Bioremediation processes have been credited for reducing high levels of organic contaminants from soils. However, during bioremediation of diesel contaminated soils, for instance, diesel is converted to volatile organic compounds (VOC) and greenhouse gases (GHG), which means that such remediation technique contributes to the greenhouse effect. The ongoing construction of a large petrochemical industrial region in Rio de Janeiro Metropolitan Area (COMPERJ) and the transportation of large volumes of oil byproducts (mainly diesel), have raised deep concerns regarding accidents that may result in soil and air contamination. When the problem comes, remediation techniques shall be applied. The objective of this study was to characterize the emission of GHG and VOC during bioremediation of soils contaminated with diesel oil in pilot scale. Soil samples contaminated with 0.5, 2.0 and 4.0 w/w% diesel oil were kept during 3 months in glass rectors (2 L internal volume) kept under anaerobic/anoxic conditions. The soil moisture was controlled at 80% of field capacity. Bioremediation processes were investigated with nutrient’s adjustment (biostimulation), no adjustment (natural attenuation) and sterilized soil (abiotic process). The gases emitted from different reactors were collected in activated carbon cartridges and the GHG were collected in Tedlar bags. The chemical analyzes were performed using a gas chromatograph (Agilent 7690) with multi-detection using FID for CH4, ECD for N2O and TCD for CO2. VOC were analyzed using a mass spectrometry detector (Varian 450GC MS220). The results indicated that gaseous samples contained high concentrations of CO2 but low concentrations of CH4 and N2O. The differences in composition of the gas emitted from the reactors regarding CO2 were statistically not significant. Preliminarily, regarding VOC emissions, such as alkanes and alkenes (both branched), cycloalkanes, and aromatic substituted (such as ethyl benzene), the compounds with higher emissions were cycloalkanes and branched alkanes.

The disposal of municipal waste in open areas, due to its varied composition, including heavy metals, constitutes a potential source of environmental risk. These areas occur several plant species that may pose potential for use in phytoremediation. The objective was to determine the level of soil contamination by heavy metals and identify plant species with potential fitoextratora in the Aura dump area, metropolitan region of Belem/PA. We determined the total concentration of heavy metals in soil and shoots five plant species: Cassia alata, Cecropia pachystachya, Ipomoea asarifolia, Piper hispidinervum and Solanum paniculatum. The bioconcentration factor of metals was calculated. On average, the levels of copper (Cu) , zinc (Zn) , lead (Pb) and cadmium (Cd) are above the reference values of soil quality for the state of Para, while Cd levels are above prevention values established by the National Environmental Council. The values of bioconcentration of Cd showed greater variation between species, from 0.32 to 0.61 mg kg-1 for Solanum paniculatum and Cassia alata, respectively, and the Cassia alata and Piper hispidinervum species showed the highest values for Zn, 0.38 and 0.44 mg kg-1, respectively. The Cassia alata showed the highest bioconcentration factor for Cd. The garbage disposal in the area contributed to the contamination by heavy metals, however the predominant species in the area did not behave as fitoextratora.Keyword: Bioconcentration factor, enrichment factor, Aura dump

Saco do Mamanguá” is located in Ilha Grande Bay, west coast Rio de Janeiro State and suffers intense pressure degradation, mainly by speculation to build "resorts". The region is extremely vulnerable, given that there are in the region of Ilha Grande bay potentially polluting enterprises, such as mangroves. Samples of surface sediments were collected in “Saco do Mamanguá”. In this region, samples were collected at five sampling points parallel to the shoreline at a distance of approximately 10 m between them. Subsequently dried, sieved and analyzed for physico-chemical characterization and determination of heavy metals: Cd, Cr, Ni, Pb and Zn after digestion with aqua regia assisted by microwave radiation. The metal concentrations were determined by atomic absorption spectrometry with flame. The results showed that the sediments in “Saco do Mamanguá” mangrove presents average levels of Cd, Ni and Pb above the established as criteria for sediment quality by environmental agencies from Canadia and United States of America, demonstrating its vulnerability to contaminants of heavy metals existing in the Bay of Ilha Grande.

The distribution of fallout 137 Cs in soil samples of the Rio de Janeiro State was investigated. Two-hundred sixty-two samples of soil were analyzed for 137 Cs by gamma spectrometry. A reference data set was built containing thirty-six detected values (14%) and two hundred twenty-six (86%) multiple detection limits of non-detected observations. Distribution pattern of the radionuclide, as well their controlling factors were evaluated based on statistical methods for censored data set (with non-detected observations). The mean of concentration values of thirty-six detected observations was 1.25 Bq.kg -1 , while for the censored data sets the mean value was 0.51 Bq.kg -1 . The references values for the Rio de Janeiro State were estimated as 1.44 Bq.kg -1 (75 th ) and 1.78 Bq.kg - 1 (90 Th ) (considering the year of 2015). 137 Cs concentrations tend to be higher in soils with high levels of organic matter and clay and locations with high levels of these parameters would provide higher Cs fixation. No influence of the rainfall index and soil pH on the Cs content in soil was observed. The data and information gathered in this study provide valuable information for decision making purposes in case of soil contamination.