Prospecção dendrocronológica de espécies tropicais e o papel das coleções de madeira como infraestruturas científicas

Abstract

Trees record the history of their interactions with the environment in anatomical structures within the wood, which give rise to growth layers. In the tropics, the high diversity of species and their species-specific climatic responses result in growth layers being demarcated by combinations of anatomical markers with varying degrees of clarity, which complicates their interpretation using dendrochronological approaches that do not account for these particularities. Given that the proportion of tropical species with confirmed dendrochronological potential remains limited, xylaria play a strategic role by preserving catalogued wood specimens suitable for supporting exploratory screening efforts. This dissertation therefore aimed to examine wood collections from two complementary perspectives: as material resources for selecting species with dendrochronological potential and as scientific infrastructures for knowledge production. In the first chapter, the anatomical markers associated with the delimitation of growth layers were characterized in wood samples from 42 tropical species housed in the Dr. Valmir Souza de Oliveira Xylarium, 12 of which lacked prior anatomical description in the consulted literature. The analysis integrated macroscopic and microscopic parameters, including the distinctness and contrast of the layers, the diagnostic value of the markers, and their expression intensity in the wood. This approach enabled the identification of 14 specimens with high preliminary anatomical suitability for future dendrochronological validation, 17 with moderate suitability, and 11 with low suitability. In the second chapter, metadata from 98 documents retrieved from the Scopus and Web of Science databases were analyzed through scientometrics in the R environment to quantify scientific output, assess research impact, and map collaboration networks. The results revealed a thematically diverse field marked by asymmetries in impact and showed that the role of xylaria has been redefined in recent decades in response to regulatory changes and technological innovations. Together, both chapters support the conclusion that the scientific relevance of xylaria lies in the articulation between rigorous curation and analytical use, a necessary condition for these collections to meet the contemporary demands of science.