Ecophysiology & Structure:
Epiphytic versus Crustose Lichens of the Atacama Fog Desert
Patrick Jung1, Lena Weber1, Lukas Lehnert2, Philippe Clerc3, Claudia Colesie1, Burkhard Büdel1
1TU Kaiserslautern, 2Philipps-University Marburg, 3 CJB, Genéve, corresponding author: firstname.lastname@example.org
The Atacama desert in Chile is one of the driest and probably oldest deserts on Earth. To survive in these conditions
life must adapt to very low water availability due to the almost complete absence of rain and high solar radiation.
Only a few extremophile organisms are able to conquer this habitat with different strategies.
How are photobiont orientation and structural features of the thallus
influencing the photosynthetic activity of the chlorolichens?
Can crustose (Acarospora cf. socialis & Caloplaca sp.) and epiphytic
chlorolichens (Pseudevernia sp. & Ramalina peruviana) reach a positive
net photosynthesis based on high relative air humidity?
Confocal laser scanning
CO2 gas exchange measurements
Saturation by high relative air humidity
Water dependent photosynthetic response at 17°C
Hyperspectral reflectance measurements
Epiphytic Lichens: Activation by high relative air
humidity. Water captured out from fog is assumed to be
the predominant water source. Loose fungal medulla
and a centered air cavity optimize gas exchange of the
aggregated photobiont. In comparison, positive net
photosynthesis is increased by more than 10x, which is
also visible in the hyperspectral chlorophyll signal.
Crustose Lichens + Substrate: No positive net
photosynthesis by high relative air humidity. The
predominant water source is expected to be morning
dew, linked to short activity periods. Higher photobiont/
fungus ratio + densely packed algal layers, protected from
solar radiation, are strategies to promote photosynthesis.
Hyperspectral chlorophyll signal and CO2uptake are low.
Can hyperspectral remote sensing data be used as a proxy for
Epiphytic Chlorolichens Crustose Chlorolichens + Substrate