External energy and plankton: New insights on the role of small-scale turbulence on zooplankton ecology

Resum

Some of the already known effects of small scale turbulence on zooplankton populations maintained in laboratory rnicrocosms (higher development rates, changes in the demographic composition of populations, higher ammonia concentration) seemed to be a cons.equence of increased energy expenditure driven by behavioural changes. Higher frequency of escape reactions and fast swimming in copepods could be the main reasons for it, although direct measurements of metabolic rates under turbulence were not available. Here we discuss the effects of small scale turbulence on two parameters directly related to metabolic activity: heart-beat rate on pond cladocerans, and NH4-N and P04-P excretion rates on marine copepods.