2013). When considering that dehydration usually occurs during long periods of sunshine, an overlap with protective and repair strategies against click here UVR, as described above, occurs. Conclusions Green algae are abundant in alpine BSCs of the Alps. Due to the spatial structure of the soil crusts, protection against direct sunlight including UV-B can be expected, which together with sufficient moisture will assure the long-term survival of these organisms, often under harsh environmental conditions. Since the Selleck NU7441 meteorological data clearly indicate the existence of highly variable

seasonal and diurnal fluctuations in radiation, sunshine duration, precipitation and air temperature (Körner 2003), it can be assumed that dehydration will affect the alpine soil crust organisms on a short-term rather than

on a long-term scale. Alpine BSC green algae are excellent model selleck systems to study and understand the protective mechanisms against UVR and desiccation. Certain algae contain the capacity to adapt in the long run to their environment, which implies that they could also function as good indicator organisms. This is important in terms of any changes in precipitation or temperature that might be associated with the future scenarios of climate change. It would be particularly interesting to study if, e.g., desiccation-tolerant green algae replace non-desiccation-tolerant ones in certain habitats. With new developments in genomics, proteomics and metabolomics, the underlying biosynthetic

and regulatory pathways can be elucidated. Such studies are urgently needed to provide a deeper insight into the mechanisms involved in the astonishing very stress tolerance of these organisms. Acknowledgments This work was supported by the Deutsche Forschungsgemeinschaft (DFG) (KA899/16-1/2/3/4) to UK, as well as by the Austrian Science Fund (FWF) grant P 24242-B16 to A.H. The authors thank Christine Kitzing, University of Rostock, for providing the physiological and biochemical data on Klebsormidium fluitans ASIB V103. Open AccessThis article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited. References Aigner S, Remias D, Karsten U, Holzinger A (2013) Unusual phenolic compounds contribute to the ecophysiological performance in the purple-colored green alga Zygogonium ericetorum (Zygnematophyceae, Streptophyta) from a high-alpine habitat. J Phycol 49:648–660CrossRef Allakhverdiev SI, Kreslavski VD, Klimov VV, Los DA, Carpentier R, Mohanty P (2008) Heat stress: an overview of molecular responses in photosynthesis.