Temporal changes of microbial respiration of leaf litter during gut passage by two species of bibionid flies (Penthetria holosericae, Bibio marci) and immediately after defecation were studied as well as the effect of B. marci feeding on microbial respiration in the remaining consumed leaf litter. Respiration in the guts of both species was lower than respiration of the original leaves.
Microbial respiration increased after defecation, but respiration was higher in comparison with the original litter only for B. marci. Later, microbial respiration in both species decreased dramatically over several hours.
Respiration of the remains of consumed leaves, from which the excrements were removed, was significantly higher than the respiration of non-consumed leaves.