Traceability of Manilkara huberi Using Stable Isotope Ratio Analysis to Support Deforestation Prevention in the Amazon

Abstract 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.