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Summary

Wood has been historically used to build traditional boats in Brazil. The present study examined different types of wood used in the boat collection of the Museu Nacional do Mar (Portuguese for National Museum of the Sea). Samples were collected with a Pressler borer and incorporated into the JOIw xylarium. Histological and anatomical descriptions followed usual wood anatomy protocols. Wood of 15 species of low, medium, and high density was microscopically identified. Most of the species are native to forests that surround the waterways where the boats were built, although some were imported from more distant forests. We believe the wood anatomy shows the relationship between human societies and forest resources used in navel carpentry. Additionally, wood surveys like this broaden our knowledge on the cultural heritage, ethnobotanic, and technological properties knowledge, which ultimately contribute to biodiversity conservation.

In: IAWA Journal

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.

In: IAWA Journal

Summary

Identification of wood formation, cell wall deposition, lignification, and the maturation process contribute to a better understanding of biomass accumulation processes. Traditional methods for studying xylem development are limited by dyeing effects and discrimination experience, are non-quantitative for the degree of cell wall deposition and lignification, or are unsuitable for broad-leaved trees. In this study, we integrated several already existing methods to improve the discriminative accuracy of the cell development stage and to quantitatively describe the cell wall deposition and lignification degree for both softwood and hardwood tree species. To do this, we collected tree microcores every 7–14 days during a growing season for two species, one conifer (Platycladus orientalis) and one broad-leaved tree (Acer truncatum), in the mountainous areas in Beijing, China. We tracked the xylem development using semi-thin section technology combined with polarization microscopy. This integrated approach allows a quantitative description of the xylem cell wall deposition and lignification process of both hardwood and softwood tree species. This approach can be applied to demonstrate the dynamic process between the cambium layer and the production of wood cells and to describe the cell wall deposition and lignification process of wood cells from generation to maturation. This approach has certain application prospects for exploring scientific issues related to wood formation and accumulation processes in forestry and ecological studies.

In: IAWA Journal

Summary

Molecular research has shown that the genus Acacia is in fact polyphyletic. The discussion about grouping the species of Acacia s.l. into monophyletic genera kept two International Botanical Congresses (Congresses 17 and 18) occupied and resulted in the general acceptance of the genera Acacia, Acaciella, Mariosousa, Senegalia and Vachellia. This raises questions about whether the wood of these new genera can be distinguished using established wood identification methods. Anatomical features of members from Acacia, Acaciella, Senegalia and Vachellia were examined and compared using transmission light microscopy. Topochemical characteristics were investigated using UV microspectrophotometry (UMSP) to identify differences in the distribution of phenolic compounds and cell wall lignification. The current study shows that the presence as well as the arrangement and dimensions of the axial parenchyma, as well as the height and width of the wood rays and fibre dimensions allow anatomical differentiation of the species studied. UMSP revealed the presence and distribution of phenolic compounds and differences in the degree of lignification between the genera. The aim of this paper is to highlight the potential of the applied methods to differentiate between the genera.

In: IAWA Journal

Summary

Spiral grain refers to the helical patterns formed by the wood grain in the trunks of many tree species. In most gymnosperms, grain near the pith is vertical but wood formed after several years of growth has a slight to pronounced left-handed twist. Grain changes presumably involve the slow rotation of cells within the vascular cambium, but the mechanisms that allow this reorientation to occur remain unclear. Understanding this process is, however, important as the presence of strong spiral grain within the corewood of gymnosperms is a major wood quality issue devaluing cut timber. In this study, we measured wood grain in stems of Pinus radiata (radiata pine) saplings through reconstructions of resin canals that follow the grain, visualised by serial sectioning and scanning with circularly polarised light, and through X-ray computed microtomography (μCT) and image analysis in ImageJ. Vertical trees retained a symmetrical grain pattern that was weakly right-handed near the pith, but which became progressively more left-handed during the first eight months of growth. In tilted trees, however, the development of left-handed grain was inhibited by the formation of compression wood on the lower side of the tree whereas the wood on the upper side of the tree developed increasingly more left-handed grain as in the vertical controls. These results demonstrate that a previously unidentified link exists between compression wood formation and the inhibition of grain development.

In: IAWA Journal
Encounters across Arts, Sciences and Humanities
Experimental Practices seeks to develop the status of science, art, and literature as truly experimental practices and forms of knowledge production – each borrowing from the other in order to further its drive to invention and innovation.
In times of environmental, political, and technological transformation and crisis, the urge to forge new alliances between the humanities, arts, and sciences has given rise to disciplinary hybrids, such as the environmental humanities, the medical humanities, artistic research, or the neurohumanities – all of which signal a turn towards ecological, more-than-human and posthumanist approaches in resonance with a broad array of worldly concerns. In this context, Experimental Practices is a platform for experimental forms of research at the intersections of the humanities, sciences, as well as activists outside academia around issues that shape contemporary and future cultures.
Taking “experimentation” as the practice, topic, and aim of the series, the editors welcome monographs or collected volumes around a specific concept or theme that contribute and enact a practice-based as well as theory-driven poetics of knowledge.
The series is committed to continue a fruitful collaboration with the international SLSA (Society for the Study of Literature, Science, and the Arts), including its independent European branch SLSAeu.

Authors are cordially invited to submit proposals and/or full manuscripts to the publisher at BRILL, Christa Stevens.

Summary

The anatomical study of wood used in Brazilian heritage, in association with other areas of knowledge, has provided important information about the cultural and social aspects of past generations and the composition and use of the flora of different regions. Our goal was to identify the wood used in the construction of two old bridges for the transport of people and cargo between Vila Dois Rios and Praia da Parnaioca, Ilha Grande, Angra dos Reis, state of Rio de Janeiro, Brazil. Anatomical features of the sampled woods were used for taxonomic identification by multiple-entry key for wood identification, followed by comparisons with anatomical descriptions of wood samples from xylarium, the literature, and databases. The search for information considered the common and/or scientific names of taxa attributed to the woods from the bridges, and whose natural occurrence is registered for Ilha Grande and/or the state of Rio de Janeiro. The results showed that the bridges were built with the wood of Zollernia ilicifolia (Brongn.) Vogel and Handroanthus sp. Mattos. Knowing that the site had labor, infrastructure, and raw materials during the period when the bridges were built, the results reveal aspects of the composition of the current and past flora of Ilha Grande.

In: IAWA Journal

Summary

Wood identification is a crucial step to verify claims of the legality of wood and wood-derived products for compliance with the laws against illegal logging. For accurate determination of wood species, transmitted light microscopy has been utilized to identify microscopic features of wood from microscopic slides with thin sections from the transverse, radial, and tangential planes. When there are many woods in trading for identification, producing microscopic or permanent slides can be problematic because the production of the slides is time-consuming and slows down wood identification. However, the slides are not required for alternative microscopy such as epi-illumination light microscopy. In this study, we suggest the utilization of epi-illumination light microscopy as an alternative method to conventional transmitted light microscopy with microscopic slides for wood identification. We investigated the performance of selected epi-illumination light microscopic techniques: brightfield reflected light microscopy with a polarizer (RLBF), darkfield reflected light microscopy (RLDF), and fluorescence light microscopy by observing intervessel pits and vessel-ray pits. Among the selected epi-illumination light microscopy, brightfield reflected light microscopy with a polarizer produced images with small details and high contrast. Since sample preparation for reflected light microscopy can be minimized, we can accelerate the wood identification process without sacrificing accuracy. We confirmed that reflected light microscopy has sufficient performance with simple sample preparation comparable to transmitted light microscopy.

In: IAWA Journal
This interdisciplinary volume of essays explores how the notion of time varies across disciplines by examining variance as a defining feature of temporalities in cultural, creative, and scholarly contexts. Featuring a President’s Address by philosopher David Wood, it begins with critical reassessments of J.T. Fraser’s hierarchical theory of time through the lens of Anthropocene studies, philosophy, ecological theory, and ecological literature; proceeds to variant narratives in fiction, video games, film, and graphic novels; and concludes by measuring time’s variance with tools as different as incense clocks and computers, and by marking variance in music, film, and performance art.
Author: David Wood

Abstract

J. T. Fraser articulates five different organizational levels of time: proto-temporality (disconnected fragments of time); eotemporality (physics, the fourth dimension); biotemporality (self-organization, life, direction); and nootemporality (human mind, including language). He later added a sixth – sociotemporality. What impact would impending catastrophic climate change have on this schematization? We argue first that, while change is central to time, change in the very shape of change marks a new threshold in Fraser’s sense. We work through what it means to be a passive spectator to radical transformation, how our human experience of time is intrinsically tied up with language, representation, and money (can we afford to prevent the end of the world?), and the impact of a shrinking future horizon on our identity, on the Enlightenment project, and on any hope of progress. Finally, inhabiting time historically is subject to many strange loops, including the breakdown of the inductive assurances that the past traditionally supplied. Extending Fraser’s scheme and (following Keller’s adumbration of a kairological time), we endorse the possibility and indeed necessity of a new threshold, a new temporal dispensation.

In: Time in Variance