Photosynthesis of lichens from lichen-dominated communities in the alpine/nival belt of the Alps – II: Laboratory and field measurements of CO2 exchange and water relations

Interspecific differences in photosynthetic efficiency and spectral reflectance in two Umbilicaria species from Svalbard during controlled desiccation

“…Dehydrationdependent decrease in photochemistry leads to the decline biochemical part of photosynthesis as proven by numerous gas exchange studies in desiccating lichens in a laboratory (e.g. Lange et al 2001) or in the field (Reiter et al 2008). Such dehydration-dependent decrease in photosynthesis is accompanied by the activation of protective mechanisms that protect components of photosystem II from damages.…”

The Influence of Biological Soil Crusts on Soil Characteristics along a High Arctic Glacier Foreland, Nunavut, Canada

“…This feature opens an additional source of water for thallus hydration to the lichens and may offer new insights into the ecology of Psora decipiens-dominated BSC from other habitats as well. Reiter et al (2008) compared the alpine and maritime Antarctic environments using standard meteorological data and suggested the main differences to be the much higher precipitation and light in the Alps and much more stable conditions in the maritime Antarctic. The comparison made in the present study benefits from measurements of in situ activity and microclimate data from BSCs at the alpine and Antarctic sites and allows a more informed comparison.…”

“…Reactivation during foggy and very cloudy conditions seems to be a common feature for BSCs in both ecosystems, where it caused 50% of the reactivation events in Garwood Valley, 40% at the Hochtor, and 64% at the Hoher Sonnblick (Reiter et al, 2008; Table 1). These conditions always coincided with low light availability and therefore resulted in low, but positive net photosynthesis.…”

“…Additional studies cover short time periods (Sancho et al, 1997;Kappen and Redon, 1987;Kappen, 1990Kappen, , 2000 or refer more to differences in snow resistance between higher plants and lichens (Kappen, 1993) than to possible water sources and activity periods within the lichens. Contributions to the knowledge about photosynthetic activity of alpine lichens have been made by Lange (1965), Heber et al (2000), Türk (2000a, 2000b), and Reiter et al (2006). However, detailed knowledge about lichen activity under natural conditions is, to our knowledge, rare (e.g., Reiter et al, 2008).…”

“…Contributions to the knowledge about photosynthetic activity of alpine lichens have been made by Lange (1965), Heber et al (2000), Türk (2000a, 2000b), and Reiter et al (2006). However, detailed knowledge about lichen activity under natural conditions is, to our knowledge, rare (e.g., Reiter et al, 2008). The authors focus on rock inhabiting species (Brodoa atrofusca and Xanthoria elegans) and additionally compared the alpine and maritime Antarctic environments using standard meteorological data, showing much higher precipitation and light in the Alps and much more stable conditions in maritime Antarctica.…”