The Society for the Protection of Underground Networks (SPUN) is a science-based initiative to map and protect the mycorrhizal networks that regulate the Earth's climate and ecosystems.[1]
The organization was founded in 2021.[2][3][4][5][6][7] The Executive Director is Toby Kiers, an evolutionary biologist at the Vrije Universiteit Amsterdam.[8] The stated goals of The Society for the Protection of Underground Networks (SPUN) are mapping,[9][10][11][12] protecting,[13][14][15] and harnessing[16][17] mycorrhizal fungi.
The Society for the Protection of Underground Networks samples soil and extracts and sequences fungal DNA in order to learn which fungi are present. The geo-located fungal taxa are then fed into a machine learning model that predicts belowground fungal biodiversity on a global scale.[18]
In order to identify mycorrhizal fungi present at a given location, The Society for the Protection of Underground Networks takes soil samples for analysis.
To date, SPUN has organized expeditions in Ecuador, Colombia, Italy,[19] Palmyra Atoll,[20] Chile,[21] Kazakhstan,[22] Corsica,[23] Ghana,[24] and Lesotho.[25] A number of factors are considered when choosing expedition locations, including sampling intensity at a location, predicted biodiversity, and feasibility of permitting. Locations or eco-regions that have had less intense sampling in the past are given priority.
SPUN follows a standardized sampling protocol (see External links below) for collecting soil samples. Soil cores are taken at nine points in a geolocated grid. These soil cores are then homogenized into a single soil sample. Metadata concerning botanical life, land use, and collaborators are recorded.
In a lab, fungal DNA is extracted from the soil samples. This DNA is sent to be sequenced and then run through a bioinformatics pipeline that assigns a fungal taxon to each sequence present.
The geo-located fungal taxa from the samples are then fed into a machine learning model that predicts below-ground fungal biodiversity on a global scale.[18] These maps are used to determine future expedition locations and provide recommendations for conservation priorities.
In June 2023 The Society for the Protection of Underground Networks scientists and collaborators published a paper that estimates that 13 billion tons of CO2 is allocated to mycorrhizal fungi annually.[26]
In addition to SPUN-led sampling efforts the organization runs a program called Underground Explorers,[27] that funds mycorrhizal research in under explored regions. As of August 2024 the program has awarded grants to 92 researchers in 43 different countries.[28] 82% of grantees are based in the Global South.