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Summary

A splinter of charred wood was recovered from late Early Eocene volcanoclastic deposits underlying the lacustrine succession of the Messel-pit near Darmstadt (Hesse, Germany). Well-preserved anatomical details due to charring allow for an attribution of the splinter to the Oleaceae family. Within Oleaceae, the wood shows good agreement with the anatomical structure of recent members of the genera Olea, Chionanthus and Noronhia. However, due to the high variability of structural features within this group of genera, a reliable taxonomic placement is restricted to the monophyletic drupaceous subtribe Oleinae. The Splinter was cut loose from a tree of the local vegetation and charred by effects of the respective phreatomagmatic eruption, even under a low-fire regime. The specimen represents a rare example of a Pre-Quarternary wood that can be related directly to a radiometric age of 48.27–48.11 Ma (±0.22 Ma).

In: IAWA Journal

Summary

Forest fires play a significant role in the growth and development of trees because they can damage the phloem and cambium. Fire injury induces the formation of fire scars that can cause xylem dysfunction. The study area is located in Taşköprü, Kastamonu (Western Black Sea of Turkiye), where two forest fires occurred in 1957 and 2020. In this study, the effect of the 1957 fire on the tree-ring widths and tracheid dimensions of Pinus nigra trees was investigated. We measured tree-ring widths and tracheid dimensions of fire-scarred (FS) and unscarred (UF) trees during four different periods: the pre-fire period (1947–1956), fire event year (1957), and post–fire periods (1958–1967 and 2011–2020). In this study, UF trees showed almost 2.5–3 times wider tree–ring widths (TRWs) than FS trees. FS and UF trees also showed great variation in tracheid dimensions in the four different periods; the average tracheid diameter (TD), lumen area (TLA), and wall thickness (TWT) values increased significantly in UF trees compared to FS trees during the fire event and post-fire periods. The average TD, TLA, and average tracheid lumen diameter (TLD) decreased during the fire and post-fire years in the FS trees. In this study, we suggest that fire injury significantly affects the tracheid dimensional traits of FS Pinus nigra trees. Our results also suggest that although Pinus nigra trees experienced serious fire damage, they continued to grow but with a decrease in tracheid size.

In: IAWA Journal
Being Algae
Open Access
Transformations in Water, Plants
Water plants of all sizes, from the 60-meter long Pacific Ocean giant kelp (Macrocystis pyrifera) to the micro ur-plant blue-green algae, deserve attention from critical plant studies. This is the first book in environmental humanities to approach algae, swimming across the sciences, humanities, and arts, to embody the mixed nature and collaborative identity of algae.
Ranging from Medieval Islamic texts describing algae and their use, Japanese and Nordic cultural practices based in seaweed and algae, and confronting the instrumentalization of seaweed to mitigate cow methane release and the hype of algal photobioreactors, amongst many other standpoints, this volume comprehensively addresses the ancestors of terrestrial plants through appreciating their unique aquatic medium.

Abstract

Humans have interacted with algae for millennia. This paper describes the human journey in the company with algae from the earliest days of our species until today where the need for a green transition and sustainable eating behaviour has put renewed focus on algae as a material of many uses not least as foodstuff. The evolution of Homo has been shaped by our ancestors being seashore dwellers with plenty of access to marine foodstuff that contains critical nutritional elements for the evolution of the large human brain. Being at the bottom of the food web, algae are the source of nutrients, e.g., the precious super-unsaturated fatty acids, that pile up through the food chains, but it starts with the marine algae. Algae have during times been a rich source for human activities as a material of unique composition and multiple uses. Algae are currently in focus as a green, sustainable food source because algae are at the base of the trophic web, feeding directly off the sun. Macroalgae (seaweeds) in particular have influenced human life conditions both on evolutionary timescales as well as in recent centuries and all the way into the Anthropocene. No wonder that these organisms have entered human mythology, folklore, poetry, art, and gastronomy. This paper will focus on two often overlooked facets of algae, which have been of key importance for their interwoven relationship with humans: their beauty and their taste.

Open Access
In: Being Algae
Authors: and

Abstract

To lay the foundations for the Biocene, a potential future era of our Anthropocene human habitat, the infrastructure of our built environment should play a more active role in carbon mitigation and reduction. Algae and cryptogrammic species will become important elements of bio-integrated “photosynthetic cities”. However, to realise this, we will need to relinquish notions of monoculture and purity associated with highly maintained and controlled cultivation. This chapter will look back at the origins of contained microalgal culture in the realms of science and engineering to understand the basis for our current design language. We assume the position that in future, consortia-based approaches with direct exposure to the outdoor environment will be required in order to deliver the vision of algae for bioremediation or microbiome-inspired green infrastructure in a resilient way. Ultimately, our photosynthetic human habitat will embody a more provocative and disobedient condition. Reconciling with the abject nature of biofouling, overcoming disgust and ultimately reaching an acceptance of the sublime will be needed in order to form ecologically relevant and environmentally meaningful interventions. The role of design will be pivotal to introduce a new aesthetic which is based on how we embrace self-regenerative conditions while promoting heterogeneity and biodiversity in buildings.

Open Access
In: Being Algae
Author:

Abstract

Lake Akan, located on Japan’s northernmost island of Hokkaido, is home to world famous algae: spherical-shaped growths of Aegagropila linnaei known in Japanese as marimo (and sometimes called “moss balls” in English). Marimo have become a charismatic species internationally, a rare feat for an alga. Lake Akan hosts an annual three-day Marimo Festival, which began in 1950 as a way of drawing attention to the endangered species and as a means of celebrating the culture of the Indigenous Ainu community in the wake of settler colonialism. A key element to marimo’s popularization is a widely-circulated story – a purported Ainu folktale that tells of two young, star-crossed lovers who jump into Lake Akan and become marimo. This tale has been used for decades to promote tourism to the Lake Akan area. However, in 2017, algae researcher Wakana Isamu traced the origins of the tale back to a Japanese writer named Nagata Kōsaku, who invented the tale and falsely claimed its Ainu origins in 1924. This chapter asks what it means for this tale of imagined indigeneity to have been embraced and reclaimed by the Ainu community of Kushiro in the name of conservation twice-over – that of rare algae and Ainu identity itself.

Open Access
In: Being Algae
In: Being Algae

Abstract

Algae in the wild form consortia with other species which promote their own health and proliferate food sources. The recent increase in laboratory algae cultivation in commercial photobioreactors (PBR) so far has focused mainly on propagating single species of algae, rather than multi-species polycultures. Considering the current status of sterile PBR ecological habitat, the chapter investigates rearranging PBR set-up to take into account algal communication within and across species. These mutualistic species form the ‘phycosphere’: the microenvironment surrounding microalgal cells, potentiating the production of certain metabolites through interaction with cohabitating microorganisms. Better understanding the phycosphere prompts PBRs to become attentive to and incorporate algal-microbial consortia, to better arrange conducive habitats for algal flourishing as interspecies symbionts. From a multisolving approach, this may decrease the inputs needed for artificially maintaining growth-systems, moving from status quo sterility to multispecies co-maintenance. PBR polycultures also invite us to reconsider the role water plays within aquaculture, teaching us to appreciate water health and diversity, as has been done with soil.

Open Access
In: Being Algae
Author:

Abstract

The chapter uses a poetic, autophenomenographic text, which contemplates the cliffs of the Danish island Fur, built by fossilized micro-algae of the group diatoms, as an entrance point to a reflection on a planetary ethics of companionship. Rather than approaching the 55 million year old diatomite cliffs as material from which to extract value, it is suggested that they should be seen as wise ancestors, who can teach us lessons about life, death and time. The chapter, firstly, gives a brief introduction to diatom biology and the geohistory of diatomite (sediments of fossilized diatoms), to the author’s intimate feelings of companionship with alive and fossilized diatoms, and to the posthuman autophenomenographic methodology which guides her contemplations of diatoms. Secondly, the author discusses the revised understandings of life, death, and time which her efforts to corpo-affectively empathize (symphysize) with alive and dead diatoms helped her to establish. She accounts for the ways in which these revisions are sustained by a vitalist materialist and immanence philosophical approach. In an open-ended conclusion, she suggests an ethics of planetary companionship, based on the contemplations of the bonds, she has established with the diatoms.

Open Access
In: Being Algae
In: Being Algae