One of the fundamental fungal actors in any terrestrial ecosystem is the mycorrhizal fungi. These fungi extend in the soil forming an underground mass of branching threadlike structures that enable the transfer of compounds between plants (Beiler et al. 2009). Mycorrhizal associations support plant fitness by facilitating the access and transfer of nutrients, and by sharing phytochemical signals among nearby plants (Tedersoo et al. 2021). These soil-based interactions enable the creation of underground mycelial networks that build tree connectivity. Tree connectivity helps foster healthy communities that form interspecific relationships among tree species and with other organisms in the soil resulting in increased ecosystem function and resilience (Horton et al. 2015).
With restoration efforts presently being conducted above ground in urban environments to enable green spaces to flourish and thrive, we realize that we have been overlooking the critical underground actors that contribute to the wellbeing of our urban ecosystems. Landscape designers have been integral in trying to help fill the knowledge gaps in understanding urban soils and designing novel interactions. But the fact still remains, humans have evicted soil fungi from our urban environment. With our obsession towards industrialization and urbanization, we have built underground infrastructure that has taken the place of underground microorganisms such as mycorrhizal fungi that are vital to the survival of plant species above ground. How can fungi reclaim underground space in the urban ecosystem?
This research will help demonstrate that one of the key ways to re-integrate mycorrhizal networks and therefore overall health of the urban biota is by redesigning underground environments. Urban infrastructure has overtaken all available space replacing what once was natural, with industrial grade construction material that is void of life. How would the structure of tree pits and sidewalks need to be redesigned to include mycorrhizal networks? This research will be expressed through the exploration, creation and implementation of design frameworks in urban spaces that will re-visit existing infrastructure and design new landscapes that ‘make room’ for mycorrhizal fungi.