https://www.alice.cnptia.embrapa.br/alice/handle/item/106 Artigo em periódico indexado (CPATU) 2026-06-12T00:37:49Z https://www.alice.cnptia.embrapa.br/alice/handle/doc/1187384 Título: From deforestation to regeneration: How do land-use changes shape soil microbes and methane-cycling genes in the Eastern Amazon? Autoria: MANDRO, J. A.; GONTIJO, J. B.; NAKAMURA, F. M.; BORGES, C. D.; OLIVEIRA JUNIOR, R. C. de; BERENGUER, E.; BOHANNAN, B. J.; NÜSSLEIN, K.; RODRIGUES, J. L. M.; TSAI, S. M.; VENTURINI, A. M. Conteúdo: Land-use change in the Amazon Rainforest impacts soil properties and belowground microbial communities, with far-reaching implications for soil ecosystem services, including methane cycling processes. However, it is unclear whether the known methane sink-to-source shift observed after forest-to-pasture conversion occurs consistently throughout the year, or whether forest regeneration can help restore this crucial ecosystem process. Here, we assessed the impacts of forest-to-pasture conversion and forest regeneration in the Amazon Rainforest on its soil properties and microbial communities, focusing on methane-related microbiota, using 16S rRNA sequencing and quantitative real-time PCR. Conversion resulted in significant changes in soil chemistry and microbial communities, while seasonality and its interaction with land use intensified these differences. Land-use change also increased the abundance of methanotrophs and methanogens, but the ratio between both groups was altered, consistent with pastures as potential sources of methane and forests as sinks. Seasonality further increased the impact of the conversion on methane-cycling microorganisms. Our findings also highlight the potential of passive forest regeneration to restore certain soil chemical and microbiological patterns similar to those of primary forests, including methane-related genes. Although these results provide strategies to support methane mitigation, they indicate that the functional and taxonomic potential of microbial communities may not be equally recovered. This highlights the importance of maintaining primary forests to preserve critical ecosystem services. 2026-01-01T00:00:00Z https://www.alice.cnptia.embrapa.br/alice/handle/doc/1187378 Título: Biomassa microbiana como bioindicador da qualidade do solo em agroflorestas cacaueiras e vegetações secundárias na Amazônia brasileira. Autoria: CICRETA, T. N.; RUIVO, M. de L. P.; BENTES, M. P. de M.; MEDEIROS, A. de S.; JR., M. M.; SILVA, B. S. F. da; OLIVEIRA, I. A. de; KATO, O. R. Conteúdo: Os Sistemas Agroflorestais com Cacau (SFACs) e vegetações secundárias (VS) amazônicas desempenham papel crucial na recuperação de solos degradados por meio da biomassa microbiana do solo (BMS), que regula a ciclagem de nutrientes e a qualidade biológica. O objetivo foi avaliar a BMS, por via carbono microbiano (MBC), nitrogênio microbiano (MBN) e razão C:Nmic, como indicador da qualidade biológica em SAFCs de diferentes idades e VS em estágios sucessionais distintos, no estado do Pará. Amostras de solo coletadas em quatro profundidades foram analisadas quanto a textura, pH e BMS (por irradiação- extração), com testes univariadas, correlação de Spearman e Análise de Componentes Principais (PCA). O uso do solo influenciou significativamente MBC e MBN (ρ ≤ 0,05), com valores máximos de 1.885,24 ±393,49 mg C kg⁻¹ para MBC e 48,46 ± 1,96 mg N kg⁻¹ para MBN. SAFCs mais antigos e VS na fase de estabilização apresentaram maiores teores, especialmente em solos mais argilosos com pH elevado. A razão C:Nmic variou de 5,52 ±0,14 a 104,22 ±22,90, refletindo diferenças na qualidade da matéria orgânica do solo (MOS) e eficiência microbiana. A PCA revelou separações edáficas claras entre regiões, associando maiores MBC e MBN a texturas argilosas. Conclui-se que SAFCs orgânicos bem manejados e maduros podem igualar ou superar a qualidade biológica de VS avançadas, sendo MBC, MBN e C:Nmic indicadores sensíveis e eficazes para monitorar trajetórias sucessionais e orientar estratégias de manejo e restauração dos solos amazônicos. 2026-01-01T00:00:00Z https://www.alice.cnptia.embrapa.br/alice/handle/doc/1187329 Título: Efeito do fotoperíodo no ciclo biológico de Diatraea saccharalis. Autoria: PARRA, J. R. P.; MELO, A. B. P.; MAGALHÃES, B. P.; SILVEIRA NETO, S.; BOTELHO, P. S. M. Conteúdo: RESUMO - A pesquisa foi desenvolvida em sala com temperatura não controlada e constou de duas etapas, a primeira realizada em um período mais frio (m=23,3oC). As observações foram conduzidas em equipamento desenvolvido no Departamento de Entomologia da Escola Superior de Agricultura Luiz de Queiroz, sendo estudada a influência dos seguintes tratamentos, em horas (luz: escuro): 0:24; 6:18; 12:12; 14:10; 18:6 e 24:0. As lagartas de Diatraea saccharalis, (F., 1794), em número de duas por tubo de criação, foram mantidas em dieta artificial, num total de 100 lagartas por tratamento. Houve interação da temperatura e fotoperíodo, principalmente nas temperaturas mais baixas. Assim, na primeira etapa da pesquisa, o menor período larval foi registrado no tratamento 24:0, enquanto que na segunda etapa, o mais curto período ocorreu com 12 horas de luz. Em ambas as situações, as pupas mais leves e a maior percentagem de deformação de adultos foram obtidas com 24 horas de luz, sendo as pupas mais pesadas registradas nos tratamentos 0:24 e 12:12. Por outro lado, as menores deformações de adultos foram encontradas com 18 e 12 horas de luz, conforme o laboratório apresentasse, respectivamente, menores ou maiores temperaturas. ABSTRACT - This work was carried out in the laboratories of the Department of Entomology of ESALQ - USP, State of São Paulo, Brazil, with photoperiod equipment developed there. This research was divided into two phases: the first under a low temperature condition (mean of 23.3 0C) and the second in a high temperatura room (mean of 26.40 C). The followinq treatments were studied (photophase: scotophase): 0:24; 6:18; 12:12; 14:10; 18:6 and 24:0. Diatraea saccharalis (F., 1794) (two larvae/container) were maintained inside glass containers with artificial diet, in a total of 100 per treatment. There was an interaction between photoperiod and temperatura, mainly at the lower temperatures. Therefore, in the first phase of the experiment, it was observed that the shortest larval period occured in the 24 hour photophase treatment; but in the second phase the shortest larval period occured in the 12:12 treatment. In both situations, the light pupae and the great percentage of adult malformations were obtained in the 24 hour photophase treatment, with the 0:24 and 12:12 photoperiodic conditions presenting the highest pupae weights. On the other hand, the shortest adult malformation percentage was observed at the 18:6 and 12:12 treatments, in both phases of the research. 1983-01-01T00:00:00Z https://www.alice.cnptia.embrapa.br/alice/handle/doc/1187224 Título: Dendrochronology of the Brazil nut tree (Bertholletia excelsa Bonpl.) in the Amazon: water memory and vulnerability of radial growth to precipitation deficit. Autoria: ARAÚJO, A. J. C.; OLIVEIRA JUNIOR, R. C. de; SANTOS, D. B. dos; COSTA, P. da; MONTEIRO JUNIOR, M. B.; MOURA, Q. L. de; VIEIRA, T. A.; REIS, B. S. dos; PAULETTO, D. Conteúdo: Understanding the growth dynamics and climatic sensitivity of Bertholletia excelsa (Brazil nut tree) is essential for assessing tropical forest resilience and recent hydroclimatic variability in Amazonia. Despite its ecological and socioeconomic importance, dendrochronological information for this species remains limited, particularly regarding the mechanisms linking large-scale climate forcing to local growth responses. In this study, we developed and evaluated growth-ring chronologies from adult B. excelsa trees in native Amazonian forests to assess growth coherence and the strength of climatic signals. Ring widths were cross-dated using COFECHA, and chronology quality statistics—effective interseries correlation (rbar.eff), expressed population signal (EPS), signal-to-noise ratio (SNR), and first-order autocorrelation (AC)—were calculated using the dplR package in R. The master chronology exhibited strong internal coherence (rbar.eff = 0.38–0.46) and a robust common signal (EPS > 0.85; SNR > 5.0), confirming reliable cross-dating and representativeness at the population level. Moderate autocorrelation values indicated physiological persistence associated with hydrological memory. Radial growth was strongly controlled by hydroclimatic variability, with precipitation emerging as the primary limiting factor and temperature acting mainly as a stressor. Growth responses were particularly sensitive during the transition from the dry to the rainy season, when cambial reactivation and earlywood formation occur. Large-scale oceanic forcing associated with ENSO and Tropical Atlantic variability influenced growth indirectly by modulating local precipitation regimes and dry-season severity, resulting in lagged growth responses following drought events. These findings demonstrate that B. excelsa integrates climatic information across the full hydrological cycle and functions as a sensitive bioindicator of recent climate variability, providing valuable insights into forest vulnerability and resilience under ongoing climate change. 2026-01-01T00:00:00Z