This paper investigates the bond behavior between a bio-aggregate and a cement-based matrix. The experimental evaluation comprised physical, chemical, image, and mechanical characterization of the bio-aggregate. The image analyses about the bio-aggregate’s outer structure provided first insights to understand the particularities of this newly proposed bio-aggregate for use in cementitious materials. A mineral aggregate (granitic rock), largely used as coarse aggregate in the Brazilian civil construction industry, was used as reference. The bond behavior of both aggregates was evaluated via pull-out tests. The results indicated that both aggregates presented a similar linear elastic branch up to each respective peak loads. The peak load magnitude of the mineral aggregate indicated a better chemical adhesion when compared to the bio-aggregate’s. The post-peak behavior, however, indicated a smoother softening branch for the bio-aggregate, corroborated by the microscopy image analyses. Although further investigation is required, the macaúba crushed endocarp was found to be a thriving bio-material to be used as bio-aggregate.

Summary The Brazilian Amazon has the world’s largest concentration of indigenous American peoples, but many environmental threats have affected the preservation of this enormous human ethnocultural heritage. This study identified the species and studied the different uses of wood by two indigenous ethnic groups in Southeastern Pará, Brazil, namely the “Gavião” and “Suruí”. Ten taxa were identified, distributed in eight botanical families, with five being identified to genus and five to species levels. The wood of Bertholletia excelsa, an endangered forest species in Brazil, is important in the material culture of the Suruí indigenous people. The indigenous ethnic groups studied preferentially use medium density wood for building and high-density wood for hunting and warfare artefacts. The technological properties of wood justify its use by the indigenous peoples studied. We caution that the increasing environmental threats in Indigenous Lands within the Brazilian Amazon harm the preservation of the ethnocultural heritage of indigenous peoples.

Protected areas in the Brazilian Amazon suffer from conflicting activities, such as the production of charcoal from illegal logging. Charcoal anatomy is an important tool that can be useful for forensic charcoal identification and to help the conservation of these areas. To assist in combating deforestation in protected areas, this study describes the charcoal anatomy of 14 tree species that occur in the Tapirapé–Aquiri National Forest, Pará, Brazil, and provides macrographs of transverse surfaces and scanning electron microscope (SEM) images to aid government agencies during surveillance. We adopted a carbonisation method that simulated real conditions. Anatomical features were well preserved in the charcoal. The axial parenchyma and vessel frequency are easily observed in both macrographs and SEM images, so they are important diagnostic features for initial screening of families and for checking the load according to the ‘document of forestry origin’ (DOF) by the surveillance agents. Uncommon and highly diagnostic features for distinguishing genera or even species, such as rays exclusively uniseriate, sheath cells, tile cells and storied structure, were observed only in SEM images. Our findings are suitable to provide a database on charcoal anatomy of native tree species of the Amazon, with practical application in government inspection activities in protected areas in Brazil and other countries with similar issues.

The objective of this study is to evaluate the characteristics of polymeric composites containing different bean residue levels for polymer replacement. To this end, agricultural residues were first reduced to particles and characterized "in natura" through tests for moisture content, bulk density, content of extractives, lignin and ash and by thermogravimetry technique. Then, particles of both materials were dried and selected based on their granulometric fractions to make low-density polyethylene (LDPE) composites with substitution levels of 0, 10, 20, 30 and 40% bean residues. The polymeric material and the bean stem and pod particles were hot-extruded to obtain strands and then pellets; the resulting materials were then molded and hot-pressed. After fabrication, the specimens were subjected to physical testing for humidity, density, water absorption, and flammability and to mechanical testing for tensile strength. Scanning electron microscopy (SEM) was performed to evaluate the fracture regions of the specimens that were broken during mechanical testing. The results indicated that the physical–mechanical properties of the composites were negatively affected by the characteristics of the lignocellulosic material and by the increased number of pores caused by the presence of the waste material.