The effect of temperature on the respiration rate of meiofauna

The effect of temperature on respiration rate has been established, using Cartesian divers, for the meiofaunal sabellid polychaeteManayunkia aestuarina, the free-living nematodeSphaerolaimus hirsutus and the harpacticoid copepodTachidius discipes from a mudflat in the Lynher estuary, Cornwall, U.K. Over the temperature range normally experienced in the field, i.e. 5-20° C the size-compensated respiration rate (R _c) was related to the temperature (T) in °C by the equation Log₁₀ R _c=-0.635+0.0339T forManayunkia, Log₁₀ R _c=0.180+0.0069T forSphaerolaimus and Log₁₀ R _c=-0.428+0.0337T forTachidius, being equivalent toQ ₁₀ values of 2.19, 1.17 and 2.17 respectively. In order to derive the temperature response forManayunkia a relationship was first established between respiration rate and body size: Log₁₀ R=0.05+0.75 Log₁₀ V whereR=respiration in nl·O₂·ind^-1·h^-1 andV=body volume in nl.TheQ ₁₀ values are compared with values for other species derived from the literature. From these limited data a dichotomy emerges: species with aQ ₁₀≏2 which apparently feed on diatoms and bacteria, the abundance of which are subject to large short term variability, and species withQ ₁₀≏1 apparently dependent on more stable food sources.