Introduction to lichens
Course description
The aim of the course is to provide new PhD students and postdoctoral researchers who, in some way, include lichens in their studies with an introduction to various aspects of lichen symbiosis, morphology and ecology. Participants may not have worked with lichens before, or may have worked only on a particular aspect of lichens, and wish to gain a broader general understanding of lichens as a subject of scientific research.
Course facts
P000192, Introduction to lichens, 3.0 Hp
Print syllabus
Syllabus
Level
Third cycle
Subject
Biology
Grading Scale
The grade requirements within the course grading system are set out in specific criteria. These criteria must be available by the course start at the latest.
Course language
English
Entry Requirements
Participants are expected to read literature prior to the course.
Objectives
After successfully completing the course, participants will have an understanding of:
- current knowledge of lichen symbiosis, lichen morphology, and modes of reproduction and dispersal
- lichen ecology, ecophysiology and taxonomy
- lichen species that are common and characteristic, as well as species of conservation concern, in different habitats in the boreonemoral and boreal regions of Sweden
- key aspects related to lichens and nature conservation
- techniques for lichen identification, including chemical analysis using HPTLC.
Content
Schedule
Friday 25 September
Excursion to Dalarna together with the course “Cryptogams and nature conservation”. We meet at Uppsala railway station and start drive from here 08.00. We will visit forests along the way and arrive Ludvika around 21.00.
Saturday 26 September
08.15-18.00 Excursion in Mt. Gyllbergen N of Ludvika.
19.00-Dinner prepared by G. Thor (vegan or vegetarian)
Sunday 27 September
Excursion back to Uppsala which we will arrive around 17.00.
Monday 28 September
09.00-11.30 Excursion to Krusenberg Castle. Lichens on old, broadleaved deciduous trees.
11.30-12.30 Lunch
13.30-17.00 Checking lichens under dissecting microscopes and microscopes. Discussions on lichens.
**Tuesday 29 September **
09.00-10.30Introductionto the more theoretical part of the course. All participants introduce themselves, including a brief description of their current research projects (5 minutes per person, followed by a few minutes of discussion).
10.45-12.00 What is a lichen and the use of lichens by other organisms including humans.
To read:
Ament-Velásquez, S.L., Tuovinen, V., Bergström, L., Spribille, T., Vanderpool, D., Nascimbene, J., Yamamoto, Y., Thor, G. & Johannesson, H. 2021. The Plot Thickens: Haploid and Triploid-Like Thalli, Hybridization, and Biased Mating Type Ratios in Letharia. Frontiers in Fungal Biology 2:656386. doi: 10.3389/ffunb.2021.656386
Grube, M., Berg, G. (2009) Microbial consortia of bacteria and fungi with focus on the lichen symbiosis. Fungal Biology Reviews 23: 72-85.
Spribille, T., Tuovinen, V., Resl, P., Vanderpool, D., Wolinski, H., Aime, MC, Schneider, K., Stabentheiner, E., Toome-Heller, M., Thor, G., Mayrhofer, H., Johannesson, H., McCutcheon, J.P. 2016. Basidiomycete yeasts in the cortex of ascomycete macrolichens. Science 253: 488-492. doi: 10.1126/science.aaf8287
Thor, G., Johannesson, H. & Tuovinen, V. 2017. Vad är en lav? Fauna & Flora 112(2): 22–26.
Tuovinen, V., Ekman, S., Thor, G., Vanderpool, D., Spribille, T. & Johannesson, H. 2019. Two Basidiomycete fungi in the cortex of wolf lichens. Current Biology 29: 1–8. https://doi.org/10.1016/j.cub.2018.12.022
11.30-12.30 Lunch
12.30-15.00 Lichen floras, lichen thallus morphology and anatomy (reproduction, growth, dispersal strategies).
To read:
any lichen flora
15.00-17.00 Checking lichens under dissecting microscopes and in microscopes.
**Wednesday 30 September **
09.00-11.30 Lichen ecophysiology (pigments and lichen substances), ecology and taxonomy, species concepts, how many species, genera, families and orders are there?
To read:
Bäcklund, S., Jönsson, M., Strengbom, J., Frisch, A. & Thor, G. 2016. A pine is a pine and a spruce is a spruce – the effect of tree species and stand age on epiphytic lichen communities. *PLoS ONE *11(1): e0147004.
Ertz, D., Guzow-Krzemińska, B., Thor, G., Łubek, A. & Kukwa, M. 2018. Photobiont switching causes changes in the reproduction strategy and phenotypic dimorphism in the Arthoniomycetes. *Scientific Reports 8:4952. *DOI:10.1038/s41598-018-23219-3.
Klein, J., Low, M., Thor, G., Sjögren, J., Lindberg, E. & Eggers, S. 2021. Tree species identity and composition shape the epiphytic lichen community of structurally simple boreal forests over vast areas. PLoS ONE 16(9): e0257564. https://doi.org/10.1371/journal.pone.0257564
Klein, J., Thor, G., Low, M., Sjögren, J. Lindberg, E. & Eggers, S. 2020. What is good for birds is not always good for lichens: Interactions between forest structure and species richness in managed boreal forests. Forest Ecology and management 473: 118327.
Myllys, L., Svensson, M., Kantvilas, G., Sérusiaux, E., van den Boom, P., Aptroot, A., Cezanne, R., Eichler, M., Pino-Bodas, R., Printzen, C., Pykälä, J., Thor, G., Westberg, M., Weber, L. & Kantelinen, A. 2026. The first comprehensive multilocus phylogeny of the lichenized genus Micarea (Ectolechiaceae, Ascomycota). Taxon**75(1): e70087
Ranius, T., Hämäläinen, A., Sjögren, J., Hiron, M., Jonason, D., Kubart, A., Schroeder, M., Dahlberg, A., Thor, G. & Jonsell, M. 2019. The evolutionary species pool concept does not explain occurrence patterns of dead-wood-dependent organisms: implications for logging residue extraction. Oecologia 191: 241–252. doi: 10.1007/s00442-019-04473-2.
Svensson, M., Johansson V., Dahlberg A., Frisch A., Thor, G. & Ranius, T. 2016. The relative importance of stand and dead wood types for wood-dependent lichens in managed boreal forests. Fungal Ecology 20: 166–174.
Thor, G., Johansson, P. & Jönsson, M. T. 2010. Lichen diversity and red-listed lichen species relationships with tree species and diameter in wooded meadows. Biodiversity & Conservation**19: 2307–2328.
11.30-12.30 Lunch
12.30-17.00 Performing HPTLC. Checking lichens under dissecting microscopes and microscopes. Using identification keys in lichen floras to identify lichen species.
Thursday 1 October
09.00-11.30 lichens in urban areas. Why use lichens in monitoring? Lichens and climate change. Lichens in the Swedish Red list and in which habitats does red-listed lichens in Sweden occur. How does tree diseases affect the lichen flora.
To read:
Jönsson, M.T. & Thor, G. 2012. Estimating Coextinction Risks from Epidemic Tree Death: Affiliate Lichen Communities among Diseased Host Tree Populations of Fraxinus excelsior. PLoS ONE* 7(9)*: e45701.doi:10.1371/journal.pone.0045701
Larsson Ekström, A.L., Sjögren, J., Boberg Djupström, L., Thor, G. & Löfroth, T. 2023. Reinventory of permanent plots show that kelo lichens face an extinction debt. Biological Conservation 288: 110363. https://doi.org/10.1016/j.biocon.2023.110363
Ohmura, Y., Thor, G., Frisch, A., Kashiwadani, H. & Moon, K. H. 2014. Increase of lichen diversity in the Imperial Palace Grounds, Tokyo, Japan. *Memoirs of the National Science Museum, Tokyo *49: 193–217.
Spribille, T., Bunnell, F. L., Thor, G., Goward, T. & Björk, C. R. 2008. Lichens on dead wood: species-substrate relationships in the epiphytic lichen floras of the Pacific Northwest and Fennoscandia. Ecography**31: 741–750.
Sundberg, S., Sandström, J. & Thor, G. 2020. Kunskapssammanställning av almens betydelse för andra arter. Länsstyrelsen i Gotlands län, rapporter om natur och miljö 2020:8.
Weber L, Niittynen P, Kantelinen A (2026) Lichens in times of climate change – impacts and responses especially in boreal and polar ecosystems. MycoKeys 128: 29–72. https://doi.org/10.3897/ mycokeys.128.173708
11.30-12.30 Lunch
12.30-17.00 Checking lichens under dissecting microscopes and microscopes. Discussions on lichens. Course evaluation
Examination Formats and Requirements for Passing the Course
**Examination: **All students are required to give an oral presentation linking their own research to a lichenological topic. Students are also expected to participate actively in discussion groups and to attend all lectures.
Responsible Department/Equivalent
Department of Ecology
Supplementary information
Other Information
To bring: All participants are expected to bring a hand lens of good quality.
To read:
Ament-Velásquez, S.L., Tuovinen, V., Bergström, L., Spribille, T., Vanderpool, D., Nascimbene, J., Yamamoto, Y., Thor, G. & Johannesson, H. 2021. The Plot Thickens: Haploid and Triploid-Like Thalli, Hybridization, and Biased Mating Type Ratios in Letharia. Frontiers in Fungal Biology 2:656386. doi: 10.3389/ffunb.2021.656386
Grube, M., Berg, G. (2009) Microbial consortia of bacteria and fungi with focus on the lichen symbiosis. Fungal Biology Reviews 23: 72-85.
Spribille, T., Tuovinen, V., Resl, P., Vanderpool, D., Wolinski, H., Aime, MC, Schneider, K., Stabentheiner, E., Toome-Heller, M., Thor, G., Mayrhofer, H., Johannesson, H., McCutcheon, J.P. 2016. Basidiomycete yeasts in the cortex of ascomycete macrolichens. Science 253: 488-492. doi: 10.1126/science.aaf8287
Thor, G., Johannesson, H. & Tuovinen, V. 2017. Vad är en lav? Fauna & Flora 112(2): 22–26.
Tuovinen, V., Ekman, S., Thor, G., Vanderpool, D., Spribille, T. & Johannesson, H. 2019. Two Basidiomycete fungi in the cortex of wolf lichens. Current Biology 29: 1–8. https://doi.org/10.1016/j.cub.2018.12.022
Location: The course is hosted by the Department of Ecology, Swedish University of Agricultural Sciences (SLU), Uppsala. It will begin with an excursion to boreal forests near Ludvika on September 25–27. The more theoretical part of the course will take place at the Department of Ecology, SLU from Monday 28 September to Thursday October 1. The course is funded by the research school Ecology – basics and applications.