Field measurement of the photosynthesis of mosses with a portable CO2 porometer at Langhovde, East Antarctica

The photosynthesis of mosses was measured with a portable CO_2 porometer (modified Koito KIP9000) at Langhovde, East Antarctica in January 1988. An assimilation chamber, 10cm×10cm×6.5cm, which was made for this measurement, was used in collecting data for 9h in Sample 1 and 11h in Sample 2. Samples were mixed communities of Bryum pseudotriquetrum and Ceratodon purpureus (Sample 1) and C. purpureus (Sample 2) collected in the Yukidori Valley, Langhovde. Both samples had high respiration rates. Net photosynthetic rates were negative at low irradiance and changed to positive rates at high irradiance. Maximum photosynthetic rates were higher than those of other mosses measured with other equipment (analyzer : Horiba VIA-300,assimilation chamber : Koito MC-A3W) in the Yukidori Valley in the same period (Y. INO : Ecol. Res., 5,195,1990)