The novel Grit Crust: Taxonomy and Recovery of Atacama’s Dark Life (GRIT LIFE)

• Applicant: Dr. Patrick Jung
• Subject Area: Ecology and Biodiversity of Plants and Ecosystems ; Physical Geography
• Term: from 2021 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 455698839

• Final Report Year: 2024

Final Report Abstract

The so-called grit crust represents a recently discovered type of biocrust situated in the Coastal Range of the Atacama Desert (Chile) made of microorganisms growing on and in granitoid pebbles, resulting in a checkerboard pattern visible to the naked eye on the landscape scale. This microbiome fulfills a broad range of ecosystem services such as bioweathering, carbon fixation and initial pedogenesis, all driven by photosynthetic activity. The main goals of the projects were to understand the microbial biodiversity and its spatio- temporal dynamics e.g. the recovery potential of the grit crust after disturbance. To tackle this we combined a recovery experiment over two years on 11 sites with 22 plots of one square meter, each with isolationand metabarcoding techniques. In addition, micro-climate- and further abiotic data on several soil properties were generated. During the project more than 300 isolates comprising many new species of free-living cyanobacteria, green algae and fungi as well as lichen-photobionts were generated and their phylogenetic position was elaborated, which supported and corrected the generated metabarcoding data. It was also unveiled that the grit crust is mainly formed by a unique population of lichens of the Caliciaceae family, sharing exclusively photobionts of the green algal genus Trebouxia represented by several lineages. Comparing the organismic composition of the grit crust with other biocrusts worldwide designates the grit crust as the only known coherent soil layer with significant landscape coverage of at least 440 km2, predominantly ruled by a single symbiotic algal genus (Trebouxia). These unique characters were also reflected in the recovery of the grit crust because all data such as chlorophyll-, carbon-, nitrogen- and DNA content as well as ecophysiological data showed that the microorganisms reached a high level of recovery after a period of two years with recolonization of each plot. As first author, I have published 16 international peer-reviewed publications in Q1 journals as part of the grant. As a co-author, I was involved in a further 7 peer-review publications. Furthermore, I was able to acquire several complementary grants (INCb, Carl- Zeiss Wildcard) and establish an international network for research on cyanobionts with over 21 cooperation partners from 11 countries.

Publications

• 2.3 Lichens as pioneers on rock surfaces. Life at Rock Surfaces, 141-160. De Gruyter.
  Jung, Patrick & Büdel, Burkhard
  
• Emendation of the Coccoid Cyanobacterial Genus Gloeocapsopsis and Description of the New Species Gloeocapsopsis diffluens sp. nov. and Gloeocapsopsis dulcis sp. nov. Isolated From the Coastal Range of the Atacama Desert (Chile). Frontiers in Microbiology, 12.
  Jung, Patrick; Azua-Bustos, Armando; Gonzalez-Silva, Carlos; Mikhailyuk, Tatiana; Zabicki, Daniel; Holzinger, Andreas; Lakatos, Michael & Büdel, Burkhard
  
• Book Chapter: Soil Algae. In: Reference Module in Earth Systems and Environmental Sciences. Elsevier.
  Bauman, K. & Jung, P.
  
• The grit crust: A poly-extremotolerant microbial community from the Atacama Desert as a model for astrobiology. Frontiers in Astronomy and Space Sciences, 9.
  Jung, Patrick; Lehnert, Lukas W.; Bendix, Jörg; Lentendu, Guillaume; Grube, Martin; Alfaro, Fernando D.; Rio, Camilo del; Gutiérrez, Alvarado José Luis; van den Brink, Liesbeth & Lakatos, Michael
  
• Chilean biocrusts: an impetus for national park management. Trends in Microbiology, 31(6), 544-547.
  Jung, Patrick; van den Brink, Liesbeth & Gutiérrez, Alvarado José Luis
  
• The dark side of orange: Multiorganismic continuum dynamics within a lichen of the Atacama Desert. Mycologia, 116(1), 44-58.
  Jung, Patrick; Baumann, Karen; Emrich, Dina; Schermer, Michael; Eckhardt, Kai-Uwe; Jandl, Gerald; Leinweber, Peter; Harion, Felix; Wruck, Andreas; Grube, Martin; Büdel, Burkhard & Lakatos, Michael
  
• Roccellinastrum, Cenozosia and Heterodermia: Ecology and phylogeny of fog lichens and their photobionts from the coastal Atacama Desert. MycoKeys, 98, 317-348.
  Jung, Patrick; Werner, Lina; Briegel-Williams, Laura; Emrich, Dina & Lakatos, Michael
  
• A direct PCR approach with low-biomass insert opens new horizons for molecular sciences on cryptogam communities. Applied and Environmental Microbiology.
  Jung, Patrick; Briegel-Williams, Laura; Werner, Lina; Jost, Emily; Schultz, Matthias; Nürnberg, Dennis J.; Grube, Martin & Lakatos, Michael
  
• The symbiotic alga Trebouxia fuels a coherent soil ecosystem on the landscape scale in the Atacama Desert. Environmental Microbiome, 19(1).
  Jung, Patrick; Brand, Rebekah; Briegel-Williams, Laura; Werner, Lina; Jost, Emily; Lentendu, Guillaume; Singer, David; Athavale, Rujuta; Nürnberg, Dennis J.; Alfaro, Fernando D.; Büdel, Burkhard & Lakatos, Michael