Diversity, ecology and age of endolithic cyanobacterial and algal communities from the Ross Desert, McMurdo Dry Valleys Antarctica

• Antragsteller: Professor Dr. Burkhard Büdel
• Fachliche Zuordnung: Physik, Chemie und Biologie des Meeres
• Förderung: Förderung von 2006 bis 2018
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 26804438

The presence of endolithic growth of pro- and eukaryotic algae in light penetrated rock parts is a common phenomenon of arid/semi-arid landscapes world wide. While endolithic communities from Antarctic sandstones are well described, our knowledge of these communities inside granite and calcite is sparse. During the field campaign 2002/2003, we found that endolithic cyanobacterial growth is much more common than previously thought in the Dry Valleys of Antarctica. 41 and 50 mg chlorophyll a/m² were determined in calcite and granite, respectively. Bonani et al. (1988) determined an age in Beacon sandstone in the order of magnitude of 10³ years. However, we determined an age of ~70 years for the granite communities. Although age measurements can only be a guess, concluded from our results, productivity must be by far higher than expected. Water is the limiting factor and we hypothesize, that in addition to snow melt, condensation by temperature reversal of substratum and air is a frequent water supply. Reports about endolithic communities in the rocks of Arctic Greenland are, to our knowledge, limited to the fossil record. A first rock sample from Greenland revealed a luxuriantly growing cryptoendolithic community dominated by green algae. We will characterize them in detail in this project. Bioalkalization due to photosynthetic activity of cyanobacteria plays a major role in the weathering of silicate rocks in the tropics and shall be another major topic here.

• DFG-Verfahren: Infrastruktur-Schwerpunktprogramme
• Teilprojekt zu: SPP 1158: Bereich Infrastruktur - Antarktisforschung mit vergleichenden Untersuchungen in arktischen Eisgebieten
• Internationaler Bezug: Neuseeland
• Beteiligte Person: Professor Dr. Thomas George Allan Green