Increasing drought pressure under anthropogenic climate change may jeopardize the potential of tropical forests to capture carbon in woody biomass and act as a long-term carbon dioxide sink. To evaluate this risk, we assessed drought impacts in 483 tree-ring chronologies from across the tropics and found an overall modest stem growth decline (2.5% with a 95% confidence interval of 2.2 to 2.7%) during the 10% driest years since 1930. Stem growth declines exceeded 10% in 25% of cases and were larger at hotter and drier sites and for gymnosperms compared with angiosperms. Growth declines generally did not outlast drought years and were partially mitigated by growth stimulation in wet years. Thus, pantropical forest carbon sequestration through stem growth has hitherto shown drought resilience that may, however, diminish under future climate change.

Amazonian oils and fats (AOFs) have promising composition and bioactive properties, and their processing with supercritical fluids presents several opportunities and challenges for the industry. Our review is dedicated to unraveling the advances in the application of supercritical fluid extraction (SFE) to produce these exceptional oils and fats from Amazonian raw materials, such as fruits, pulps, seeds, and industrial by-products. Our review found that Amazonian plant species produce lipid-rich raw materials and also grow naturally in other regions with similar climates. AOFs present high nutritional value and functional properties due to their content of bioactive compounds. The properties of AOFs are attributed to their major and minor components; lipid molecules represent the major fraction and some fat-soluble compounds, such as tocopherols, phytosterols, terpenes and others, constitute the minor fraction. The production of AOFs by SFE requires properly prepared raw materials and process optimization. Several scientific articles report on the production of AOFs by SFE, but application studies in product development are still scarce. The composition and technological properties of AOFs show a wide spectrum of opportunities for the development of nutritional and functional products. Aspects such as the scaling up of the SFE process, agroforestry or agronomic production, and product development require further studies to promote the AOFs industry in a way that contributes to sustainable development, food security, and the quality of life and health of the Amazonian populations.

El estudio de las especies que presentan potencial dendrocronológico es importante y es la base para investigaciones más complejas que ayuden a entender los bosques mediante técnicas dendrocronológicas. Evaluamos la especie Zanthoxylum rhoifolium Lam. y su potencial para estudios dendrocronológicos en la Amazonía peruana. Para dicho fin, fueron utilizados 10 árboles de Zanthoxylum rhoifolium, de ocurrencia natural en el fundo El Bosque de la Universidad Nacional Amazónica de Madre de Dios - UNAMAD, la colecta fue realizada a través del método no destructivo con el auxilio del barreno de Pressler. Se caracterizaron los anillos de crecimiento en la sección transversal de la especie, su potencial dendrocronológico, la relación de la cronología con el clima local (precipitación y temperatura) y la temperatura de la superficie del mar (SST) HadlSST1. Los resultados de la caracterización anatómica de los anillos de crecimiento de la especie de Zanthoxylum rhoifolium mostraron tener un gran potencial para estudios en dendrocronología por presentar una buena delimitación del anillo de crecimiento. Se logró construir una cronología de 32 años (1985-2017). Finalmente se pudo comprobar que la especie Zanthoxylum rhoifolium presentó respuesta significativa al clima local e influencia a SST.

The Jacaranda copaia species presented an increase in density in the bark-pith direction, while for the Hura crepitans species there was no significant variation, these variations are explained by the fiber morphology of its fibers. The biomass of wood and the biomechanics of these species since density and fibers are directly related.

Bamboos are abundant and versatile, hence their growing interest throughout the world in a variety of uses, however, there is little technical information on the anatomy and physical properties that are important to further expand and diversify its uses. For them, the objective was to characterize the anatomy and variation in the axial direction of the physical properties of the three bamboo species in the Madre de Dios region. For this, the bamboo species were collected: Bambusa vulgaris, Gigantochloa apus, and Guadua weberbaueri were through destructive methods, collecting three culms from different bushes and obtaining samples at different heights of the culm (base, intermediate and apex). The anatomy was performed at the base of the culm and the physical properties at the three axial positions. The results show that at the anatomical level, there is a difference between the three species mainly due to the vascular bundles, on the physical properties there was also a difference between species and the variation in the axial direction there was variation in the three positions, in addition, the grouping analysis showed that the species Bambusa vulgaris and Gigantochloa apu form a group due to their anatomical characteristics and physical properties, while Guadua weberbaueri was not grouped with either. Finally, the appropriate uses of the three bamboo species are directly related to their anatomy and physical properties, being key to their sustainable use in tropical forests.

El objetivo de esta investigación fue construir la cronología de los anillos de crecimiento de la especie Jacaranda copaia (Achihua), analizar con los eventos más severos del fenómeno El Niño. Para ello se colectaron 10 árboles de J. copaia, de un bosque relicto de la región de Madre de Dios en el Perú. Se obtuvieron cuatro muestras por árbol, mediante la sonda de Pressler. El proceso, medición y análisis de los anillos de crecimiento fueron realizados mediante técnicas estándar de dendrocronología. Se construyó la cronología master de J. copaia, se determinó el incremento medio anual de la especie y la cronología fue relacionada con los eventos severos del fenómeno de El Niño. Los resultados muestran que J. copaia, presentan anillos de crecimiento distinto y anuales, delimitados por zonas fibrosas, la intercorrelación del ancho de los anillos de crecimiento entre árboles fue de 0.36. La edad máxima fue de 34 años. La relación entre la cronología y los eventos más severos del fenómeno El Niño fue de 0.18 y tuvo una relación clara en el año 1998. Los resultados revelan el potencial dendrocronológico de la especie J. copaia, e los bosques tropicales de Madre de Dios y para futuros estudios dendroclimáticos.