Santiago Linorio Ferreyra Ramos

Climate change is a growing threat to the conservation of Amazonian medicinal flora, potentially altering the geographical distribution of species and compromising the availability of plant genetic resources. This study aimed to model the current and future potential distribution under different climatic scenarios of the medicinal plant species Carapa procera, Uncaria tomentosa, Ampelozizyphus amazonicus, and Vernonia polysphaera. Occurrence records from databases and scientific collections were used to model the ecological niche with six algorithms implemented in ENMTML. Future projections considered the climate models HadGEM3-GC31-LL, IPSL-CM6A-LR, and MIROC6 under the SSP2-4.5 and SSP5-8.5 scenarios for the periods 2041–2060, 2061–2080, and 2081–2100. Overall, model performance varied among species and algorithms, with higher predictive performance observed for GAU, MXD, RF, and SVM. The environmental suitability of C. procera showed reduction, while U. tomentosa showed an initial reduction followed by partial spatial redistribution. In A. amazonicus, moderate reduction was observed, mainly under the higher-emissions scenario, while V. polysphaera showed increased environmental suitability. The results indicate differences in future environmental suitability between species and provide support for planning in situ and ex situ conservation strategies and identification of potentially priority areas for the conservation of these plant genetic resources. Keywords: environmental suitability; plant genetic resources; in-situ conservation; ecological niche modeling.

Illegal deforestation represents one of the main challenges to the integrity of the Amazon rainforest, warranting the use of reliable tracking methods to identify the geographical origin of timber species inspected during commercial transactions. This study utilizes stable carbon (δ13C) and nitrogen (δ15N) isotopes to determine the origins of Manilkara huberi (massaranduba) and to establish a database of its geographical provenance. A total of 130 individual trees were sampled, yielding 350 wood samples, in the Brazilian states of Amazonas, Pará, Rondônia, and Roraima, and these wood samples were analyzed using isotope-ratio mass spectrometry. The results revealed significant differences in δ13C and δ15N isotopic signatures, which were associated with variations in soil properties, vegetation type, and local environmental conditions. Linear discriminant analysis yielded classification performance ranging from 14% to 97%, with the highest accuracies observed in specific municipalities. Nitrogen isotope ratios in the wood showed stronger geographic differentiation, whereas carbon isotope ratios reflected broader environmental influences. This study presents a georeferenced isotopic approach based on living trees, enabling Brazilian agencies to strengthen their use of this technique to combat illegal timber trade and to provide technical support for the evaluation and validation of Forest Origin Documents in Brazil.

This study evaluated the potential of Total Reflection X-ray Fluorescence (TXRF) as a geochemical traceability method for wood from Manilkara huberi (Ducke) A. Chev., a species of high commercial and ecological value widely exploited in the Legal Amazon. Wood samples were collected in eight locations in the states of Amazonas, Pará, Rondônia, and Roraima, representing different edaphic, geological, and climatic conditions in the context of Amazonian edaphic and geological variability. The multielemental analysis revealed significant variations in trace element and macronutrient concentrations (Fe, Mn, K, Ca, Sr, Rb), reflecting the specific geochemical signatures of each region. Multivariate analyses (PCA and NMDS) showed distinct groupings among the populations, confirming the discriminatory capacity of TXRF in the differentiation of geographical origins. Significant correlations between elements such as K × Rb and Cr × Fe demonstrated consistent patterns of coaccumulation and antagonism associated with local geochemistry. The results prove the efficiency of TXRF as a non-destructive, sensitive, and low-cost technique for origin authentication and forensic investigation of Amazonian wood, strengthening sustainable management policies and combating illegal exploitation. The proposed methodology is a scientific advance in forest traceability and biodiversity conservation, contributing to the transparency and legality of timber production chains in the Amazon.

Assessing climate vulnerability of tropical trees requires ecological niche modeling frameworks capable of integrating multiple sources of uncertainty. Here, we present an integrated modeling approach that combines climatic, edaphic, and topographic predictors, dimensionality reduction, multi-algorithm calibration, and ensemble forecasting to evaluate future environmental suitability under climate change. Using two Brazilian Handroanthus species as a case study, occurrence data were spatially filtered, predictors were summarized through principal component analysis, and models were built using six algorithms with performance-weighted consensus projections. Future distributions were projected for three time periods (2041–2060, 2061–2080, and 2081–2100) under intermediate and high emission scenarios (SSP2-4.5 and SSP5-8.5). The framework showed high predictive reliability and revealed contrasting vulnerability patterns, including severe suitability losses for one species and greater stability for the other across phytogeographic domains. Beyond species-specific outcomes, results demonstrate how integrated Ecologial Niche Modeling (ENM) frameworks can identify climate-driven risk gradients and support climate-informed conservation, forest management, and territorial planning in tropical regions.

O objetivo desse estudo foi avaliar o uso de solução de hipoclorito de sódio (NaClO) na assepsia e no estabelecimento in vitro de gemas apicais e axilares extraídas do talo da coroa do fruto do abacaxi da cultivar Turiaçu Amazonas. O experimento foi conduzido em delineamento inteiramente casualizado, em esquema fatorial triplo 2x3x2, com dois tipos de explante (gema axilar e gema apical), três concentrações de NaClO na solução asséptica (0,5, 1,25 e 2,5% de cloro ativo) e dois tempos de imersão dos explantes (5 e 10 minutos). Os maiores percentuais de explantes estabelecidos in vitro foram obtidos com 5 minutos de imersão na solução asséptica, na concentração de 0,5% de cloro ativo para a gema apical e de 1,25% para a gema axilar. Os tratamentos mais favoráveis resultaram no estabelecimento in vitro de 93,8% de gemas axilares e 58,3% de gemas apicais, sem contaminação ou oxidação, e aptos à micropropagação. O NaClO é eficaz na assepsia para o estabelecimento in vitro de gemas apicais e axilares extraídas da coroa do fruto do abacaxizeiro e a concentração adequada do agente asséptico depende do tipo de explante utilizado. Palavras-chave: Ananas comosus; cultura de tecidos; contaminação; oxidação.

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Coffea canephora is economically and socially important for small-scale agriculture in Northern Brazil. To identify genotypes adapted to Amazonian edaphoclimatic conditions, clones of the species have been evaluated across multiple locations in Amazonas. Introducing genetically selected materials into comparable environments may promote consistent productivity gains in the short and medium term. In this context, the aim of this study was to assess the genetic diversity of different C. canephora genotypes using microsatellite markers, which will support the development of superior genotypes adapted to Amazon conditions. A total of 43 C. canephora genotypes were analyzed. Leaves were collected for genomic DNA extraction and were standardized and amplified by PCR using microsatellite primers. Genotyping was performed via capillary electrophoresis, allowing for the determination of allele sizes. Genetic structure was inferred, and genetic diversity parameters were estimated. The average observed heterozygosity (H_O = 0.64) exceeded the expected heterozygosity (H_E = 0.53), and the average inbreeding coefficient (f = −0.19) indicated an excess of heterozygotes. The results revealed high genetic variability among the evaluated genotypes. These findings highlight the broad genetic diversity of C. canephora, reinforcing its potential as a genetic basis for selection and the development of cultivars adapted to the environmental conditions of the Amazon.

A jabuticabeira (Plinia cauliflora (Mart.) Kausel) é uma espécie arbórea nativa do Brasil, amplamente valorizada por seus frutos de elevado potencial nutricional, funcional e medicinal, além de sua importância econômica e sociocultural para pequenos produtores e comunidades tradicionais. Seus frutos e subprodutos são utilizados nos setores alimentício, farmacêutico e cosmético, o que reforça a necessidade de estratégias eficazes de conservação da espécie. Diante das mudanças climáticas globais, este estudo teve como objetivo avaliar a distribuição potencial atual e futura de Plinia cauliflora no território brasileiro, com ênfase na conservação da espécie. Para isso, aplicou-se a modelagem de nicho ecológico com base em registros de ocorrência e variáveis climáticas, edáficas e topográficas, utilizando múltiplos algoritmos e abordagem de consenso. As projeções foram realizadas para os cenários SSP2-4.5 e SSP5-8.5, nos períodos de 2041–2060, 2061–2080 e 2081–2100. Os resultados indicaram elevada adequabilidade ambiental atual nos domínios da Mata Atlântica, Cerrado e Caatinga, porém evidenciaram redução e fragmentação das áreas favoráveis em cenários futuros, especialmente sob altas emissões. Conclui-se que a espécie apresenta elevada vulnerabilidade climática, destacando a importância da modelagem de nicho ecológico como ferramenta estratégica para orientar ações de conservação.

A castanheira-da-Amazônia é uma espécie florestal de grande relevância para a conservação das florestas tropicais e como fonte de renda e alimentação para milhares de famílias agroextrativistas. Este estudo analisou a relação entre os atributos físico-químicos do solo e a distribuição espacial das castanheiras em um castanhal nativo no Amazonas. As amostras foram coletadas na Propriedade do Jutica – Tefé/AM, na camada superficial do solo (0-20 cm) de uma parcela permanente (300 x 300 m), seguindo uma amostragem sistemática com 60 pontos distribuídos a cada 50 m entre linhas e 30 m entre pontos. Todas as castanheiras com DAP ≥ 10 cm foram inventariadas, e os dados do solo foram avaliados por estatística descritiva e geoestatística. A Krigagem Indicativa foi aplicada para interpolação do DAP, separando árvores com DAP ≥ 50 cm e DAP < 50 cm. A regressão espacial foi realizada com o algoritmo Random Forest, e todas as análises foram conduzidas no software R. Os resultados indicaram um grau moderado de heterogeneidade nos atributos do solo. O modelo Random Forest gerou mapas de probabilidade que caracterizaram a distribuição espacial das castanheiras e identificaram as regiões mais propícias à ocorrência de indivíduos com diferentes classes de DAP. Os atributos mais seletivos foram cálcio, sódio, matéria orgânica, cobre, areia total e nitrogênio, evidenciando sua influência na seletividade ambiental da espécie.

A mudança climática, impulsionada pelo aumento dos gases de efeito estufa, altera os regimes térmicos e pluviométricos globais, ameaçando ecossistemas megadiversos, como a Amazônia. Espécies de Hymenaea (H. aurea, H. courbaril, H. erigyone, H. martiana, H. parvifolia, H. stigonocarpa) possuem elevado valor alimentar, madeireiro e medicinal, sendo, portanto, prioritárias para programas de conservação comunitária. Este estudo objetivou desenvolver projeções a partir da modelagem da distribuição atual (2009-2019) e futura das espécies de Hymenaea, utilizando 19 variáveis bioclimáticas e 14 edáficas em domínios fitogeográficos brasileiros. Foram geradas informações para dois cenários climáticos do SSP (Shared Socioeconomic Pathways), SSP245 (menos pessimista) e SSP585 (mais pessimista), nos intervalos de tempo 2041-2060, 2061-2080 e 2081-2100. Os modelos indicam alta adequabilidade nos domínios Amazônia, Cerrado e Caatinga; contudo, cenários futuros predizem contrações de áreas significativas, sobretudo no SSP585, com perdas progressivas de habitat adequado. SSP245 sugere reduções menores e variações mais estáveis. Frente a essa tendência, propõe-se a priorização de unidades de conservação e corredores ecológicos nesses domínios, aliada a planos de manejo sustentáveis que integrem o conhecimento tradicional e a pesquisa aplicada. A integração de dados climáticos, edáficos e socioecológicos desta pesquisa fornece uma base científica robusta para o delineamento da preservação dos recursos genéticos de Hymenaea nas próximas décadas, mitigando os riscos de extinção. Palavras-chave: conservação florestal; recursos florestais; modelagem ecológica; domínios fitogeográficos brasileiros. Impacts of climate change on the distribution of jatoba species Climate change, driven by the increase in greenhouse gases, alters global thermal and rainfall regimes, threatening megadiverse ecosystems such as the Amazon. Hymenaea species (H. aurea, H. courbaril, H. erigyone, H. martiana, H. parvifolia, H. stigonocarpa) have high food, timber, and medicinal value and are therefore a priority for community conservation programs. This study aimed to develop projections from modeling the current (2009-2019) and future distribution of Hymenaea species using 19 bioclimatic and 14 edaphic variables in Brazilian phytogeographic domains. Information was generated for two climate scenarios, SSP (Shared Socioeconomic Pathways), SSP245 (less pessimistic), and SSP585 (more pessimistic), in the time intervals 2041-2060, 2061-2080, and 2081-2100. The models indicate high adequacy in the Amazon, Cerrado, and Caatinga; however, future scenarios predict contractions of significant areas, especially in SSP585, with progressive losses of suitable habitat. SSP245 suggests smaller reductions and more stable variations. Against this trend, it is proposed that conservation units and ecological corridors in these areas be prioritized, combined with sustainable management plans that integrate traditional knowledge and applied research. The integration of climatic, edaphic, and socioecological data from this research provides a robust scientific basis for the design of the preservation of genetic resources of Hymenaea in the coming decades, mitigating extinction risks. Keywords: forest conservation; forest resources; ecological modeling; Brazilian phytogeographic domains.