A RESPIROMETER FOR CONTINUOUS, INSITU, MEASUREMENTS OF SEDIMENT OXYGEN-DEMAND

The design of a respirometer for continuous, in situ measurement of sediment oxygen demand/benthic animal respiration is presented. The major advantages of the design over the existing ones are: (1) ambient environmental conditions, particularly oxygen levels, can be maintained inside the chamber throughout a prolonged measurement period; (2) the design is simple and easy to deploy and provides continuous measurements over a wide, varying range of SOD; and (3) the existing problems in estimating "optimal" chamber size to suit different SOD ranges and the undesirable effects of disturbing sediment by mixing devices inside the chamber are eliminated. Using the present design, the SOD of different sediment types was continuously measured for 6 h and the data are presented. © 1990.