Abstract
At depths of around 9, 500 meters in the Japan Trench, carbon dioxide uptake by microorganisms per liter of bottom water was found to be from 0.22 to 0.32 μg C per day at 3°C at normal atmospheric pressure (1 atm) and about 1.0 μg C per kilogram (wet weight) of bottom sediments. Such uptake of carbon dioxide by microorganisms in samples from a depth of 1, 690 meters near the Trench was found to be 0.59 μg C per liter of bottom water and about 10 μg C per kilogram of bottom sediments. Radioactive carbon was used for determining carbon dioxide uptake in the water and sediment samples shortly after their recovery during Leg IV of Scripps' Zetes (Deepac X) Expedition.
