In this project we want to assess how Sphagnum spores that disperse over long distances are affected by drought and UV stress. We also want to understand how Sphagnum spore viability (UV and drought tolerance) is related to traits such as size, color, and ultrastructure.

 

Dispersal, especially long-distance dispersal, is an important component in many disciplines within biology. Spores are one of the dispersal means used by bryophytes, contributing to species population persistence, especially in monoecious species. Bryophytes rely on different dispersal agents such as wind, water, and insects for spore dispersal. Most species have small spores, and they can be carried considerable distances by wind.

 

Peat mosses, namely Sphagnum species, are the dominant and most important carbon sequestering plants in northern peatlands. Sphagnum mosses produce large amounts of spores every year and there is increasing evidence that Sphagnum spores have a strong long distance dispersibility which is important for colonization of disturbed habitats. During long distance dispersal, Sphagnum spores are inevitably exposed to external stimuli such as ultraviolet radiation, drought and freezing.

 

At the end of July 2022, mature spore capsules of more than ten Sphagnum species were collected from five peatlands near Stockholm, Sweden. The spore capsules were stored in sealed plastic bottles in a refrigerator at 4 °C in darkness before the onset of the experiments. In the next step we will measure the spore vitality (spore UV and drought tolerance) and try to answer our questions.

 

Supervisors:

• Sebastian Sundberg, Artdatabanken, Swedish University of Agricultural Sciences

• Kristoffer Hylander, Department of Ecology, Environment and Plant Sciences, Stockholm University

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