POLAR ROCKS: Continuous monitoring of photosynthetic activity and microclimatic conditions of Andreaea gainii on Livingston Island

The Radio-PAM chlorophyll fluorometer (Heinz Walz GmbH, Germany) is a photosynthesis yield analyser optimized for field measurements that allows for the continuous in situ monitoring of indirect photosynthetic activity indicators and microclimatic conditions, in particular temperature (ºC), relative humidity (%), and photosynthetic active radiation (μmol photon · m-2 · s-1).

Two Radio-PAMs were used to conduct an approximately three-week long analysis of the metabolic activity and the microenvironmental parameters of two specimens belonging to the Antarctic moss species Andreaea gainii under natural conditions. The instruments were installed in two locations in the vicinity of the Spanish Antarctic Station Juan Carlos I on Livingston Island (South Shetland Islands, Antarctica): one in Punta Polaca (50 m.a.s.l.), and one in El Castillo Nunatak (449 m.a.s.l.). The comparative continuous monitoring of this species’ metabolic activity in its natural habitat provides detailed information on the dynamics that characterize its photosynthetic performance.
This experimental design somewhat mimics that of the Antarctic Campaign of 2021-2022, where four Radio-PAM fluorometers were installed in pairs in Punta Polaca and in El Castillo Nunatak to monitor the photosynthetic activity of the lichen species Usnea aurantiaco-atra.