Ríos, Asunción De losRaggio Quílez, JoséPérez-Ortega, SergioVivas, MercedesPintado Valverde, AnaGreen, Thomas George AllanAscaso, CarmenGarcía Sancho, Leopoldo2024-01-162024-01-162011-10de los Ríos A, Raggio J, Pérez-Ortega S, Vivas M, Pintado A, Green TGA, Ascaso C, Sancho LG (2011) Anatomical, morphological and ecophysiological strategies in Placopsis pycnotheca (lichenized fungi, Ascomycota) allowing rapid colonization of recently deglaciated soils. Flora 206:857–8640367-253010.1016/j.flora.2011.05.002https://hdl.handle.net/20.500.14352/93432The green algal lichen Placopsis pycnotheca was identified at Pia and Marinelli glaciers (Isla Grande of Tierra de Fuego, Chile) as a primary colonizer of bare soil in areas close to the front of the glacier or around small ponds created after glacier retreatment. Electron microscopy study showed that P. pycnotheca formed a thick hypothallus within which hyphae and their extracellular polymeric substances bind numerous soil particles. This structure augments water holding and soil stabilization capacities and constitutes an early stage in soil crust development. In addition, numerous cephalodia are formed within the hypothallus and subsequently develop upwards towards the thallus surface, sometimes before the formation of squamules with green algae. These anatomical and morphological strategies together with physiological properties such as the long photosynthetic activity period (measured in the laboratory) help explain its pioneering role as a colonizer and its apparently high growth rate.engjournal articlehttps://doi.org/10.1016/j.flora.2011.05.002restricted access581.4AnatomyCephalodiaGas exchangeReceding glaciersSoil crustTerricolous lichenNitrogen FixationFisiología vegetal (Biología)Botánica (Biología)2417.19 Fisiología Vegetal2417.03 Botánica General