Mycelium-based materials at the dawn of the Anthropocene

Activiteit: Talk or presentation at a conference

Description

This paper presents the first results of a method for the fabrication of biologically aug-mented materials by engaging with the unique properties of complex non-linear fungal sys-tems. We investigate the practical requirements to produce mycelium-based materials as a case-study of closed-loop materiality, focused on the importance of its terrestrial attach-ment.
Modernity leaves us with devasted landscapes of depleted resources, waste landfill, que-ries, oil platforms. Several research institutes have defined the dynamic living skin of the Earth as the Critical Zone (CZ) (Brantley et al., 2017). It refers to the layers from the top of the vegetative canopy through the soil, to the mother rocks. Within this thin and porous layer, all life exists (Arènes et al., 2018). Monitoring those complex biogeochemical reac-tions has revealed how anthropogenic forces are transforming the subsurface responses in water, regolith structure, minerals, and biotic activity to considerable depths (Brantley et al., 2017). Consequently, those changes in the co-evolving stratum, influence the plants, ani-mals and climate. The resulting fragility and exponential reactivity of the CZ have led many scientists, with Paul Crutzen as one of the firsts, to define this geological episode as the An-thropocene.
The aim of this paper is to strategize about how such observations of the CZ could inform biologically augmented matter and therefore regenerate the relationship between humans and the ecological landscape it inhabits. Our approach is the result of different years of cross-disciplinary research in growing materials as a trigger for alternative societal composi-tions. The study leads to several questions: Can the terrestrial entanglement of fungal mate-rials provide solutions to our environmental issues? Secondly, how can the complex adap-tive behaviour of these biological systems be translated to materiality? Finally, how are sev-eral mechanical and hygrothermal properties combined into one material? Answering those questions requires us to examine the parameters to which the biological organisms adapt in their environment.
Almost all of the Earth’s terrestrial fixed carbon is balanced in forests where fungi play a central role in the nutrient cycling processes (Cairney, 2005). Saprotrophic basidiomycete wood decay fungi are the only organisms that can completely decompose lignocellulose, the main component of vascular plants or humus, to provide a source of carbon and nitrogen (Boddy, 1999). By forming an interwoven three-dimensional filamentous network in the forest soil, they can persist for decades or centuries. The nutrient resources are rapidly col-onised and redistributed by the long-distance translocation activities of basidiomycete my-celia at the ecosystem scale, both horizontally across the forest soil and vertically between understorey layers (Cairney, 2005).
The environmental factors affecting the long-distance translocation activities include chemical (the type and concentration of carbon substrate, levels of nitrogen and phosphate, trace minerals, dissolved oxygen and carbon dioxide), and physical (pH, and temperature) parameters (Papagianni, 2004). As many parameters influence the interrelationships be-tween the process variables and the fungal morphology, it is arduous to fully deduce the mechanisms, also because the role of many factors is still not fully understood. It are those infinity complex, and interwoven cycles originated in the CZ that form the terrestrial at-tachment of mycelium-based materials (Figure 1).
Mycelium-based lignocellulosic materials are composed of natural reinforcement fibres and a fungal mycelium species. Together, they form an interwoven three-dimensional fila-mentous network binding the feedstock into a lightweight material. The result is a composite which is characterized by the chemical composition of the substrate and the mycelium (con-tent in chitin, lipid, polysaccharides, protein). The mycelium-based material is heat-killed after the growing process.
Although the mechanical properties described in the paper are not optimal yet for struc-tural applications, this research shows that mycelium-composite can fulfil the requirements of thermal insulation. The properties of the thermal conductivity and water absorption coef-ficient with flax and hemp fibres have shown an overall good insulation behaviour in all the aspects compared to conventional unsustainable materials.
Cross-pollination over the different fields outlined in this paper can allow us to draw the contours of future directions regarding biologically augmented materiality.
Periode25 jul 201926 jul 2019
EvenementstitelFourth International Conference on Structures and Architecture (ICSA 2019)
EvenementstypeConference
LocatieLisbon, Portugal
Mate van erkenningInternational