ABSTRACT
Microbial prey are either prelabeled or labeled while they are being grazed. The prelabeling technique requires growing microbial prey with a radioactive tracer, introducing the labeled microbe to the existing microbial community and determining the specific activity of the food source. The prelabeling technique requires growing microbial prey with a radioactive tracer, introducing the labeled microbe to the existing microbial community and determining the specific activity of the food source. The synoptic, in situ, labeling technique to measure invertebrate grazing on microbial prey has many advantages over other techniques. Microbial production and grazing impact can also be measured simultaneously. There are three size claseses of benthic organisms corresponding to bacteria, meiofauna, and macrofauna. Meiofauna are feeding during the control experiments, but microbial uptake of label is inhibited by the treatment. If a microbial inhibitor is used in control experiments, then the effectiveness of the inhibitor should be checked.
