Resumen Objetivo: Describir los objetivos, la metodología y la respuesta del estudio «Factores genéticos, ambientales y de estilo de vida asociados a la longevidad en Castilla y León» (España). Método: La Red Centinela Sanitaria estudió una muestra de personas longevas de 95 y más años de edad. Se pidió el consentimiento informado y se tomaron muestras biológicas para genotipificación, que fueron procesadas con el Global Screening Array v3.0 que contiene 730.059 marcadores. Conclusiones: Fueron contactados 944 longevos y 760 completaron el estudio. El 87,4% de los longevos habían nacido en Castilla y León, y solo el 1,5% no eran naturales. El 8,1% de los hombres y el 19,2% de las mujeres presentaban un deterioro cognitivo grave. Los médicos de familia y las enfermeras consiguen una alta participación y una buena calidad de la información en estudios de base poblacional. Se tomaron muestras de ADN en el 94% de los longevos y el 100% fueron genotipificadas con éxito.

Abstract Objective: To describe the objectives, the methodological approach, the response rate of the Genetic, Environmental and Life-style Factors Study in Castilla y León (Spain). Method: The Health Sentinel Network studied a sample of long-lived individuals aged 95 or more (LLI). The study included biological samples processed with the Global Screening Array v3.0 that contains a total of 730,059 markers. Written consent was obtained before the examination. Conclusions: The LLI contacted were 944, and 760 were completed studied. The 87.4% of LLI were born in Castile and Leon and only 1% were non-native of Spain. Severe cognitive impairment was declared in 8.1% of men and 19.2% of women. Genotyping was performed in 739 LLI, the 78.3% of the contacted sample. Family doctors and nurses achieve high participation in population-based studies. DNA samples were taken from 94% of fully studied LLI, and 100% of these samples where successfully genotyped.

Abstract Objective: To describe the objectives, the methodological approach, the response rate of the Genetic, Environmental and Life-style Factors Study in Castilla y León (Spain). Method: The Health Sentinel Network studied a sample of long-lived individuals aged 95 or more (LLI). The study included biological samples processed with the Global Screening Array v3.0 that contains a total of 730,059 markers. Written consent was obtained before the examination. Conclusions: The LLI contacted were 944, and 760 were completed studied. The 87.4% of LLI were born in Castile and Leon and only 1% were non-native of Spain. Severe cognitive impairment was declared in 8.1% of men and 19.2% of women. Genotyping was performed in 739 LLI, the 78.3% of the contacted sample. Family doctors and nurses achieve high participation in population-based studies. DNA samples were taken from 94% of fully studied LLI, and 100% of these samples where successfully genotyped.

Resumen Objetivo: Describir los objetivos, la metodología y la respuesta del estudio «Factores genéticos, ambientales y de estilo de vida asociados a la longevidad en Castilla y León» (España). Método: La Red Centinela Sanitaria estudió una muestra de personas longevas de 95 y más años de edad. Se pidió el consentimiento informado y se tomaron muestras biológicas para genotipificación, que fueron procesadas con el Global Screening Array v3.0 que contiene 730.059 marcadores. Conclusiones: Fueron contactados 944 longevos y 760 completaron el estudio. El 87,4% de los longevos habían nacido en Castilla y León, y solo el 1,5% no eran naturales. El 8,1% de los hombres y el 19,2% de las mujeres presentaban un deterioro cognitivo grave. Los médicos de familia y las enfermeras consiguen una alta participación y una buena calidad de la información en estudios de base poblacional. Se tomaron muestras de ADN en el 94% de los longevos y el 100% fueron genotipificadas con éxito.

Abstract The current COVID-19 pandemic has sharply increased pre-existing social divides. In this research, we analyzed the relationships of different facets of social class with well-being and affectivity across 8 Ibero-American countries. Moreover, we also tested the potential mediating role of perceived risk of COVID-19 and perceived collective efficacy. The results obtained (a) revealed that a lower social class was related to reduced well-being and positive affect as well as to greater negative affect, (b) confirmed that subjective social class was a better predictor of well-being and affectivity than educational level (i.e., an objective indicator of social class), and (c) showed that subjective social class was indirectly linked to well-being/affectivity via its effects on the perceived risk of COVID-19 and perceived collective efficacy. These findings support the existence of differences in well-being and affectivity as a function of social class during the pandemic, while advancing our understanding of underlying psychosocial mechanisms.

Resumen La actual pandemia de COVID-19 ha supuesto un marcado incremento de las brechas sociales preexistentes. En esta investigación analizamos las relaciones de diferentes facetas de clase social con el bienestar y afectividad general a lo largo de un total de 8 países de la región cultural iberoamericana. Asimismo, también pusimos a prueba el potencial rol mediador del riesgo percibido relativo a la COVID-19 y de la eficacia colectiva percibida. Los resultados obtenidos (a) revelaron que una clase social más baja se relacionó con un menor bienestar y afecto positivo, así como con un mayor afecto negativo; (b) confirmaron que la clase social subjetiva constituye un mejor predictor del bienestar y afectividad general que el nivel educativo (i.e., indicador de clase social objetiva); y (c) mostraron que los efectos de la clase social subjetiva en el bienestar/afectividad general se daban de forma indirecta a través del riesgo percibido y la eficacia colectiva. Estos hallazgos confirman la existencia de diferencias en bienestar y afectividad general en función de la clase social durante la pandemia, al tiempo que permiten avanzar en la comprensión de los mecanismos psicosociales subyacentes.

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Resumo Mesmo no período em que a pandemia de Covid-19 encontrava-se em crescimento no Nordeste do Brasil, iniciou-se a adoção de medidas de flexibilização do distanciamento social. O objetivo do estudo é o de avaliar a pertinência das propostas de flexibilização, tomando-se em conta a situação da pandemia em cada local e o momento em que foram adotadas. Tendo como referência as diretrizes da OMS, foram construídos e analisados indicadores operacionais para cada diretriz, no contexto da região Nordeste. Para análise do comportamento da epidemia, conforme indicadores selecionados, foram usadas técnicas de Joinpoint Trend Analysis, mapas de calor, razão de taxas e comparação da tendência temporal entre capitais e interior dos estados. O pico do crescimento semanal ocorreu em maio-julho/2020 (semanas epidemiológicas 19 a 31). Na maioria das capitais não se observou tendência decrescente simultânea do número de casos e óbitos nos 14 dias prévios à flexibilização. Em todos os estados o quantitativo de testes realizados foi insuficiente. Na semana epidemiológica 24 os percentuais estaduais de ocupação de leitos de UTI/Covid-19 foram próximos ou superiores 70%. A situação epidemiológica das nove capitais dos estados do Nordeste, no momento em que a decisão de flexibilização foi tomada, mostra que nenhuma delas atendia aos critérios e parâmetros recomendados pela OMS.

Abstract Even in the period when the Covid-19 pandemic was on the rise in the Northeast of Brazil, the relaxation of social distancing measures was introduced. The scope of the study is to assess, in the light of the epidemiological-sanitary situation in the region, the suitability of relaxation of social distancing measures. Based on the WHO guidelines for relaxation of social distancing, operational indicators were created and analyzed for each guideline in the context of the Northeast. To analyze the behavior of the epidemic, according to selected indicators, Joinpoint trend analysis techniques, heat maps, rate ratios and time trends between capitals and the state interior were compared. The weekly growth peak of the epidemic occurred in May-July 2020 (epidemiological weeks 19 to 31). In most capitals, there was no simultaneous downward trend in the number of cases and deaths in the 14 days prior to flexibilization. In all states the number of tests performed was insufficient. In epidemiological week 24, the state percentages of ICU/Covid-19 bed occupancy were close to or above 70%. The epidemiological situation of the nine Northeastern state capitals analyzed here did not meet criteria and parameters recommended by the World Health Organization for the relaxation of social distancing measures.

Resumo Mesmo no período em que a pandemia de Covid-19 encontrava-se em crescimento no Nordeste do Brasil, iniciou-se a adoção de medidas de flexibilização do distanciamento social. O objetivo do estudo é o de avaliar a pertinência das propostas de flexibilização, tomando-se em conta a situação da pandemia em cada local e o momento em que foram adotadas. Tendo como referência as diretrizes da OMS, foram construídos e analisados indicadores operacionais para cada diretriz, no contexto da região Nordeste. Para análise do comportamento da epidemia, conforme indicadores selecionados, foram usadas técnicas de Joinpoint Trend Analysis, mapas de calor, razão de taxas e comparação da tendência temporal entre capitais e interior dos estados. O pico do crescimento semanal ocorreu em maio-julho/2020 (semanas epidemiológicas 19 a 31). Na maioria das capitais não se observou tendência decrescente simultânea do número de casos e óbitos nos 14 dias prévios à flexibilização. Em todos os estados o quantitativo de testes realizados foi insuficiente. Na semana epidemiológica 24 os percentuais estaduais de ocupação de leitos de UTI/Covid-19 foram próximos ou superiores 70%. A situação epidemiológica das nove capitais dos estados do Nordeste, no momento em que a decisão de flexibilização foi tomada, mostra que nenhuma delas atendia aos critérios e parâmetros recomendados pela OMS.

Abstract Even in the period when the Covid-19 pandemic was on the rise in the Northeast of Brazil, the relaxation of social distancing measures was introduced. The scope of the study is to assess, in the light of the epidemiological-sanitary situation in the region, the suitability of relaxation of social distancing measures. Based on the WHO guidelines for relaxation of social distancing, operational indicators were created and analyzed for each guideline in the context of the Northeast. To analyze the behavior of the epidemic, according to selected indicators, Joinpoint trend analysis techniques, heat maps, rate ratios and time trends between capitals and the state interior were compared. The weekly growth peak of the epidemic occurred in May-July 2020 (epidemiological weeks 19 to 31). In most capitals, there was no simultaneous downward trend in the number of cases and deaths in the 14 days prior to flexibilization. In all states the number of tests performed was insufficient. In epidemiological week 24, the state percentages of ICU/Covid-19 bed occupancy were close to or above 70%. The epidemiological situation of the nine Northeastern state capitals analyzed here did not meet criteria and parameters recommended by the World Health Organization for the relaxation of social distancing measures.

Resumo No Brasil, a pandemia da COVID-19 tem sido severa nos estados das regiões mais pobres, como o Nordeste. A falta de políticas nacionais para controle da pandemia levou as autoridades estaduais e municipais a implementarem medidas de saúde pública. O objetivo deste estudo é mostrar o efeito dessas medidas na epidemia. A maior incidência da COVID-19 entre os nove estados do Nordeste foi registrada em Sergipe, Paraíba e Ceará. O Piauí, a Paraíba e Ceará foram os que mais testaram. Muitos estados apresentavam alta proporção de pessoas em trabalho informal. Estados com aeroportos internacionais tiveram importante papel na entrada e disseminação inicial do vírus, em especial o Ceará. Todos os estados aplicaram medidas de distanciamento social, proibição de eventos públicos e fechamento de unidades de ensino. As respostas foram o aumento significativo de distanciamento social, em especial Ceará e Pernambuco, a queda do número de reprodução (Rt) e a separação da curva dos casos observados da curva dos casos esperados sem as intervenções não medicamentosas em todos os estados. A pobreza, a desigualdade e as altas taxas de trabalho informal fornecem pistas do porquê da intensidade da COVID-19 na região. Por outro lado, as medidas de mitigação tomadas precocemente pelos governantes amenizaram os efeitos da pandemia.

Abstract The COVID-19 pandemic has been most severe in the poorest regions of Brazil, such as the states of the Northeast Region. The lack of national policies for pandemic control forced state and municipal authorities to implement public health measures. The aim of this study is to show the effect of these measures on the epidemic. The highest incidence of COVID-19 among the nine states in the Northeast was recorded in Sergipe, Paraíba and Ceará. Piauí, Paraíba and Ceará were the states that most tested. Factors associated with transmission included the high proportion of people in informal work. States with international airports played an important role in the entry of the virus and the initial spread, especially Ceará. All states applied social distancing measures, banned public events and closed schools. The response was a significant increase in social distancing, especially in Ceará and Pernambuco, a decline in the reproduction rate (Rt), and a separation of the curve of observed cases versus expected cases if the non-pharmacological interventions had not been implemented in all states. Poverty, inequality, and the high rates of informal work provide clues to the intensity of COVID-19 in the region. On the other hand, the measures taken early by the governments mitigated the effects of the pandemic.

Resumo No Brasil, a pandemia da COVID-19 tem sido severa nos estados das regiões mais pobres, como o Nordeste. A falta de políticas nacionais para controle da pandemia levou as autoridades estaduais e municipais a implementarem medidas de saúde pública. O objetivo deste estudo é mostrar o efeito dessas medidas na epidemia. A maior incidência da COVID-19 entre os nove estados do Nordeste foi registrada em Sergipe, Paraíba e Ceará. O Piauí, a Paraíba e Ceará foram os que mais testaram. Muitos estados apresentavam alta proporção de pessoas em trabalho informal. Estados com aeroportos internacionais tiveram importante papel na entrada e disseminação inicial do vírus, em especial o Ceará. Todos os estados aplicaram medidas de distanciamento social, proibição de eventos públicos e fechamento de unidades de ensino. As respostas foram o aumento significativo de distanciamento social, em especial Ceará e Pernambuco, a queda do número de reprodução (Rt) e a separação da curva dos casos observados da curva dos casos esperados sem as intervenções não medicamentosas em todos os estados. A pobreza, a desigualdade e as altas taxas de trabalho informal fornecem pistas do porquê da intensidade da COVID-19 na região. Por outro lado, as medidas de mitigação tomadas precocemente pelos governantes amenizaram os efeitos da pandemia.

Abstract The COVID-19 pandemic has been most severe in the poorest regions of Brazil, such as the states of the Northeast Region. The lack of national policies for pandemic control forced state and municipal authorities to implement public health measures. The aim of this study is to show the effect of these measures on the epidemic. The highest incidence of COVID-19 among the nine states in the Northeast was recorded in Sergipe, Paraíba and Ceará. Piauí, Paraíba and Ceará were the states that most tested. Factors associated with transmission included the high proportion of people in informal work. States with international airports played an important role in the entry of the virus and the initial spread, especially Ceará. All states applied social distancing measures, banned public events and closed schools. The response was a significant increase in social distancing, especially in Ceará and Pernambuco, a decline in the reproduction rate (Rt), and a separation of the curve of observed cases versus expected cases if the non-pharmacological interventions had not been implemented in all states. Poverty, inequality, and the high rates of informal work provide clues to the intensity of COVID-19 in the region. On the other hand, the measures taken early by the governments mitigated the effects of the pandemic.

Os media assumem um papel crítico na disseminação da informação sobre o risco alimentar, podendo o consumidor instruir-se sobre a atualidade dos diferentes perigos alimentares, recorrendo nomeadamente à leitura da imprensa escrita. A presente investigação pretendeu avaliar o modo como as notícias associadas ao risco alimentar são tratadas por um jornal diário nacional. Para o efeito, consideraram-se os títulos das suas capas, para o período de 2000 a 2017. Recorreu-se à análise de conteúdo, procurando-se identificar categorias comuns às diferentes capas, construindo-se um formulário de recolha de informação. Das 335 capas analisadas, confirmou-se que os perigos alimentares tiveram cobertura nas capas do jornal, representando cerca de 5% das capas noticiadas durante o período em estudo, sendo que o tipo de perigo mais difundido foi o biológico, seguido do perigo nutricional. Individualmente, os perigos alimentares mais abordados foram a obesidade, o vírus da gripe das aves e a BSE. Verificou-se ainda que a BSE assumiu particular importância por ser o perigo alimentar que constituiu um maior número de manchetes. A maioria das capas analisadas sobre perigos alimentares dizia respeito ao território português

The mass media plays a critical role in the dissemination of information regarding food risk, so that the consumers can learn about the current situation of the food hazards by reading the press. This research aims to evaluate how news related to food risk are handled by a daily newspaper with a national coverage. For this purpose, the titles of the covers were considered for the period from 2000 to 2017. Content analysis was used as a way to identify the same categories from the different covers, a guide was constructed for this effect. From the 335 covers analyzed, it was confirmed that the food hazards were portrayed in the covers of the newspaper, representing about 5% of the covers reported during the study period, and that the most widespread type of hazard was the biological type, followed by the nutritional hazard. Individually, the most commonly reported hazards were obesity, avian flu and BSE. It was also found that BSE was particularly important because it was the hazard that made up the biggest number of headlines. Most of the food risk covers were related to the Portuguese territory.

Epilepsy is the main cause of neurological clinical visits in Peruvian children. However, in our country, there is little information on its clinical and epidemiological characterizes. Objectives: To describe the clinical characteristics of children with epilepsy seen at the Cayetano Heredia Hospital, between 2010 and 2016. Material and Methods: A descriptive retrospective observational study was carried out, based on the clinical records of children under 14 years old with diagnosis of epilepsy, with clinical follow-up, electroencephalography and neuroimaging. Results: One hundred ninety-three patients were included. In 47.2% (91/193), the first seizure occurred before the one year of age; the etiology was secondary in 59.3% (54/91), with the main causes being perinatal events and cerebral malformations. Primary etiologies were more frequent in the children who started haviing seizures after one year of age. Generalized seizures ocurred in 64.2% (124/193) without differences by age groups. In 69.9% (135/193) seizures were controlled with a single drug while 15% (29/193) were refractory to treatment. Comorbidity occurred in 68,4% (132/193), with delays in psychomotor development, intellectual disability and cerebral palsy being frequent. Conclusions: Most children had their first seizures before the first year of age, usually with a secondary cause. In older children, the primary epilepsies were more prevalent. Monotherapy controlled the majority of children, but a percentage of refractoriness to the treatment was registered. Comorbidities were very frequent.

La epilepsia es la principal causa de consulta neurológica en niños peruanos. Sin embargo, hay escasa información sobre sus características clínicas y epidemiológicas. Objetivos: Presentar las características clínicas de los niños epilépticos atendidos en el Hospital Cayetano Heredia, entre los años 2010 y 2016. Material y métodos: Se realizó un estudio observacional descriptivo, retrospectivo, tipo serie de casos, basado en las historias clìnicas de en niños menores de 14 años con diagnóstico de epilepsia, seguimiento clínico, registro electroencefalogràfico y neuroimagenes. Resultados: Se incluyeron 193 pacientes. El 47,2% (91/193) presentaron su primera crisis epiléptica antes del año de edad, cuya etiología fue secundaria en el 59,3% (54/91), destacando los factores perinatales y las malformaciones cerebrales. La etiología primaria fue más frecuente en los niños que iniciaron las crisis después del año de edad. Las crisis generalizadas se presentaron en 64,2% (124/193) sin diferencias por grupos etarios. El 69,9% (135/193) fueron controlados con un solo fármaco, en tanto que el 15% (29/193) fueron refractarios al tratamiento. La comorbilidad ocurrió en el 68,4% (132/193), siendo frecuentes el retraso del desarrollo psicomotor, el retardo mental y la parálisis cerebral. Conclusiones: La mayoría de los niños presentaron su primera crisis antes del año de edad, generalmente de causa secundaria. En los niños mayores fue prevalente la etiología primaria. La mayoría fueron controlados con monoterapia, pero se registró un porcentaje de refractariedad al tratamiento. La comorbilidad fue muy frecuente.

Resumo Fundamento: Pacientes submetidos à ressincronização cardíaca podem evoluir com padrões de resposta acima do esperado, com normalização dos parâmetros clínicos e ecocardiográficos. Objetivo: Analisar as características clínicas e ecocardiográficas desta população de super-respondedores, comparando-as com os demais pacientes submetidos à terapia de ressincronização cardíaca. Métodos: Estudo de coorte observacional, prospectivo, envolvendo 146 pacientes, consecutivamente submetidos a implantes de ressincronizador cardíaco. Para comparação das variáveis, foram realizados o teste exato de Fisher e o teste de Mann-Whitney. Foram considerados super-respondedores os pacientes com fração de ejeção > 50 % e classe funcional I/II (New York Heart Association) após 6 meses da terapia de ressincronização cardíaca. Resultados: A idade média foi de 64,8 ± 11,1 anos, sendo 69,8% do sexo masculino, com mediana da fração de ejeção de 29%, sendo 71,5% com bloqueio de ramo esquerdo, 12% com bloqueio de ramo direito associado a bloqueios divisionais; 16,3% com marca-passo cardíaco definitivo, 29,3% com miocardiopatia isquêmica, 59,4% com miocardiopatia dilatada e 11,2% com miocardiopatia chagásica. Foram observados 24 (16,4%) super-respondedores, sendo que 13 (8,9%) apresentaram normalização da fração de ejeção, dos diâmetros diastólicos do ventrículo esquerdo e da classe funcional. Quando comparados com os pacientes não super-respondedores, em relação às características pré-implante, os super-respondedores apresentaram-se mais no sexo feminino (58,3% vs. 22,8%; p = 0,002), maior índice de massa corporal (26,8 vs. 25,5; p = 0,013), maior fração de ejeção basal (31,0 vs. 26,9; p = 0,0003) e menores diâmetros diastólicos do ventrículo esquerdo (65,9 mm vs. 72,6 mm; p = 0,0032). Dez pacientes (41,6% dos super-respondedores) com bloqueio de ramo direito e bloqueio divisional evoluíram como super-respondedores, entretanto apenas um paciente com doença de Chagas e apenas na primeira avaliação. Conclusões: Os super-respondedores apresentaram cardiopatia de base menos avançada e sem diferenças em relação ao tipo de distúrbio de condução basal. Pacientes com bloqueio de ramo direito e bloqueio divisional, mas sem cardiopatia chagásica podem também evoluir como super-respondedores.

Abstract Background: Patients submitted to cardiac resynchronization may develop response patterns that are higher than expected, with normalization of clinical and echocardiographic parameters. Objective: To analyze the clinical and echocardiographic characteristics of this population of super-responders, comparing them with the other patients submitted to cardiac resynchronization therapy. Methods: A prospective, observational cohort study involving 146 patients consecutively submitted to cardiac resynchronization implants. Fisher's exact test and Mann-Whitney test were performed to compare the variables. Patients with ejection fraction > 50% and functional class I/II (New York Heart Association) were considered super-responders after 6 months of cardiac resynchronization therapy. Results: Mean age was 64.8 ± 11.1 years, with 69.8% of males, with a median ejection fraction of 29%, 71.5% with left bundle-branch block, 12% with right bundle-branch block associated with hemiblocks; 16.3% wearing a definitive cardiac pacemaker, 29.3% with ischemic cardiomyopathy, 59.4% with dilated cardiomyopathy, and 11.2% with Chagasic cardiomyopathy. Twenty-four (16.4%) super-responders were observed, and 13 (8.9%) showed normalization of the ejection fraction, left ventricular diastolic diameters and functional class. When compared to the non-super-responder patients, in relation to the pre-implantation characteristics, the super-responders were more often females (58.3% vs. 22.8%, p = 0.002), had higher body mass index (26.8 vs. 25.5, p = 0.013), higher baseline ejection fraction (31.0 vs. 26.9, p = 0.0003), and lower left ventricular diastolic diameters (65.9 mm vs. 72.6 mm, p = 0.0032). Ten patients (41.6% of super-responders) with right bundle-branch block and hemiblock progressed to super-responders, although there was only one patient with Chagas' disease among them, and only at the first assessment. Conclusions: Super-responders had less advanced heart disease at baseline and no differences regarding the type of conduction disorder at baseline. Patients with right bundle-branch block and hemiblock, but without Chagasic heart disease may also progress as super-responders.

ABSTRACT Revegetation is essential to improve the quality of constructed soils. This study investigated effects of perennial grasses on total organic carbon (TOC) stock, organic matter (OM) fractions and on quality of a recently constructed soil, after coal mining. Soil samples were collected from the 0.00-0.03 m layer two years after the beginning of the experiment. The treatments consisted of Cynodon dactylon cv vaquero (T1); Urochloa brizantha (T2); Panicum maximun (T3); Urochloa humidicola (T4); Hemarthria altissima (T5); Cynodon dactylon cv tifton (T6); bare constructed soil (T8); and natural soil (T9). The treatments with grass species increased the TOC stock by 57 % and increased the OM lability in comparison with T8. Higher C accumulation in the coarse and free light fractions and a higher C management index were observed in T2 and T3, indicating greater suitability of these species for the initial recovery of OM of the constructed soil.

Solos construídos após mineração frequentemente apresentam baixos estoques de carbono (C) e baixa qualidade de matéria orgânica (MO). As plantas de cobertura são cruciais para o processo de recuperação desses estoques, melhorando a qualidade do solo construído. Este trabalho objetivou avaliar o efeito de coberturas vegetais sobre o estoque de C orgânico total (COT), a distribuição do C em frações físicas da MO e o índice de manejo de C (IMC) de um solo construído após mineração de carvão. O experimento foi instalado em 2003 e seis tratamentos foram implementados: Hemarthria altissima (T1), Paspalum notatum (T2), Cynodon dactilon (T3), Urochloa brizantha (T4), solo construído descoberto (T5) e solo natural (T6). Amostras de solo foram coletadas em 2009, na camada de 0,00-0,03 m, onde foram determinados o estoque de COT e o de C nas frações físicas granulométricas (carbono da fração grosseira - CFG; e carbono associado aos minerais - CAM) e densimétricas (fração leve livre - FLL; fração leve oclusa - FLO; e fração pesada - FP) da MO do solo. Os componentes do IMC: índice de estoque de carbono (IEC), labilidade (L) e índice de labilidade (IL) foram estimados a partir de ambos os métodos de fracionamento. Não foram observadas diferenças nos estoques de COT, CFG e CAM, e os menores estoques de C nas frações FLL (0,86 Mg ha-1) e FLO (0,61 Mg ha-1) foram apresentados pelo T2. Todos os tratamentos apresentaram valores intermediários de estoque de COT, C nas frações físicas e IMC, maiores que T5 e menores que T6, indicando a recuperação parcial da qualidade do solo. Em decorrência da maior adaptação das espécies Hemártria e Brizanta, resultando em maior acúmulo de material orgânico lábil, esses tratamentos apresentaram maior IEC, L, IL e IMC, sugerindo maior potencial dessas espécies para recuperação do solo construído.

Soils constructed after mining often have low carbon (C) stocks and low quality of organic matter (OM). Cover crops are decisive for the recovery process of these stocks, improving the quality of constructed soils. Therefore, the goal of this study was to evaluate the effect of cover crops on total organic C (TOC) stocks, C distribution in physical fractions of OM and the C management index (CMI) of a soil constructed after coal mining. The experiment was initiated in 2003 with six treatments: Hemarthria altissima (T1), Paspalum notatum (T2), Cynodon dactylon (T3), Urochloa brizantha (T4), bare constructed soil (T5), and natural soil (T6). Soil samples were collected in 2009 from the 0.00-0.03 m layer, and the TOC and C stocks in the physical particle size fractions (carbon in the coarse fraction - CCF, and mineral-associated carbon - MAC) and density fractions (free light fraction - FLF; occluded light fraction - OLF, and heavy fraction - HF) of OM were determined. The CMI components: carbon pool index (CPI), lability (L) and lability index (LI) were estimated by both fractionation methods. No differences were observed between TOC, CCF and MAC stocks. The lowest C stocks in FLF and OLF fractions were presented by T2, 0.86 and 0.61 Mg ha-1, respectively. The values of TOC stock, C stock in physical fractions and CMI were intermediate, greater than T5 and lower than T6 in all treatments, indicating the partial recovery of soil quality. As a result of the better adaptation of the species Hemarthria and Brizantha, resulting in greater accumulation of labile organic material, the CPI, L, LI and CMI values were higher in these treatments, suggesting a greater potential of these species for recovery of constructed soils.

Após a mineração do carvão a céu aberto, os solos são construídos e normalmente apresentam baixos estoques e baixa qualidade de matéria orgânica (MO), sendo importante usar espécies para revegetação e recuperação da área degradada. Este trabalho objetivou avaliar a distribuição do carbono (C) em frações químicas, bem como as características químicas e o grau de humificação da MO em um solo construído após a mineração de carvão e sob cultivo de gramíneas perenes. O experimento foi instalado em 2003, com os seguintes tratamentos: Hemarthria altissima (T1), Paspalum notatum (T2), Cynodon dactilon (T3), Urochloa brizantha (T4), solo construído descoberto (T5) e solo natural (T6). Em 2009, amostras de solo foram coletadas na camada de 0,00-0,03 m e determinados os estoques de C orgânico total (COT) e de C nas frações químicas: extrato ácido (CHCl), ácido fúlvico (CAF), ácido húmico (CAH) e humina (CHU). A fração ácido húmico (AH) foi caracterizada por espectroscopia de infravermelho, e calculou-se o índice de fluorescência induzida a laser (IFIL) da MO. Após seis anos, somente foram encontradas diferenças nos estoques de C da fração AH, sendo os maiores estoques observados em T1 (0,89 Mg ha-1) e T4 (1,06 Mg ha-1). Os espectros de infravermelho do AH de T1, T2 e T4 foram semelhantes ao do T6, com maior contribuição de compostos orgânicos alifáticos, em comparação ao AH dos demais tratamentos. Nesse sentido, o IFIL decresceu na sequência T5>T3>T4>T1>T2>T6, o que indica maior humificação da MO em T3 e T5 e MO mais lábil nos demais tratamentos. Sendo assim, os tratamentos T1 e T4 evidenciaram maior potencial para recuperação da qualidade da MO do solo construído.

After open coal mining, soils are “constructed”, which usually contain low levels and quality of organic matter (OM). Therefore, the use of plant species for revegetation and reclamation of degraded areas is essential. This study evaluated the distribution of carbon (C) in the chemical fractions as well as the chemical characteristics and humification degree of OM in a soil constructed after coal mining under cultivation of perennial grasses. The experiment was established in 2003 with the following treatments: Hemarthria altissima (T1), Paspalum notatum (T2), Cynodon dactilon (T3), Urochloa brizantha (T4), bare constructed soil (T5), and natural soil (T6). In 2009, soil samples were collected from the 0.00-0.03 m layer and the total organic carbon stock (TOC) and C stock in the chemical fractions: acid extract (CHCl), fulvic acid (CFA), humic acid (CHA), and humin (CHU) were determined. The humic acid (HA) fraction was characterized by infrared spectroscopy and the laser-induced fluorescence index (ILIF) of OM was also calculated. After six years, differences were only observed in the CHA stocks, which were highest in T1 (0.89 Mg ha-1) and T4 (1.06 Mg ha-1). The infrared spectra of HA in T1, T2 and T4 were similar to T6, with greater contribution of aliphatic organic compounds than in the other treatments. In this way, ILIF decreased in the sequence T5>T3>T4>T1>T2>T6, indicating higher OM humification in T3 and T5 and more labile OM in the other treatments. Consequently, the potential of OM quality recovery in the constructed soil was greatest in treatments T1 and T4.