AME 56:263-273 (2009)  -  DOI: https://doi.org/10.3354/ame01326

ABSTRACT: Net primary production and respiration were estimated in a hypersaline cyanobacterial mat colonizing a gypsum crust in the Eilat salterns, Israel. Two different approaches were used: in situ microprofiling with Clark-type O₂ sensors and application of optode sensor spots in incubation chambers. The net O₂ release rates of the mat phototrophs was high, with a maximum of 3.4 nmol O₂ cm^–2 min^–1 measured by microprofiling and 4.4 nmol O₂ cm^–2 min^–1 determined in the incubation chambers. The upper 2 layers of the mat as well as the overlying water quickly became O₂ saturated during the day. The respiration of the whole gypsum crust was also very intensive and corresponded to the O₂ produced by photosynthesis on a diurnal basis, which prevented most of the evolved O₂ from reaching the water. The results presented show that optode sensor spots are useful tools providing additional information about export and photosynthetic production rates of O₂ in hypersaline microbial mats.

KEY WORDS: Hypersaline · Gypsum crust · Microbial mat · Net production and respiration · Microelectrode · Optode

Full text in pdf format

Cite this article as: Woelfel J, Sørensen K, Warkentin M, Forster S, Oren A, Schumann R (2009) Oxygen evolution in a hypersaline crust: in situ photosynthesis quantification by microelectrode profiling and use of planar optode spots in incubation chambers. Aquat Microb Ecol 56:263-273. https://doi.org/10.3354/ame01326 Export citation Share:    Facebook - - linkedIn