Decomposers, Bacteria, and Microbenthos 363 



SEDIMENT RESPIRATION * 



Decomposition can also be examined at the level of a whole system. 

 In this section, the respiration rate of the sediments is described as a 

 measure of the microbial processes occurring. 



Methods 



Sediment respiration was determined from the accumulation of 

 inorganic carbon in Plexiglas core tubes containing undisturbed sediment 

 and overlying water. After the sediments were collected, the tubes were 

 closed at the top with a rubber stopper and incubated in situ for 4 to 6 hr. 

 An infra-red gas analyzer was used to measure the amount of carbon 

 dioxide produced during an incubation (see Reed (1974) and Miller and 

 Reed (1975) for details). 



c 



e 



c 



O ■D 

 O lO 



E e 



O <J 



100 



o> 50 

 O E 



0) 



r 80 



o 



E ^ en 



<=■ < 

 2..0 40 



20- 





 500 



400 



o 300 



T3 

 <\l 



o 200 



E 



100 



South^ 

 Shore 



.North 

 Shore 



Root 

 Zone 



FIGURE 8-6. Sediment 

 respiration, organic matter, 

 and organic content from a 

 transect in Pond A, 16 

 August 1973. 



*J.P. Reed and M.C, MUler. 



