Comparison of the response of meio- and macrobenthos to disturbance and organic enrichment

The effects of the interaction between physical disturbance and organic enrichment with respect to various aspects of subtidal meiobenthic nematode community structure have been examined in a large-scale mesocosm experiment. The relationship between meiobenthic and macrobenthic community structure within this experiment has been explored. Meiofauna and macrofauna showed similar and strongly related responses. Highest diversity was observed in treatment combinations of low levels of disturbance and enrichment and this supports the “Dynamic Equilibrium Model” of Huston [Huston, M.A., 1979. A general hypothesis of species diversity. Am. Nat. 113, 81-101.]. Faunal community structure was more variable at treatment combinations of low levels of disturbance and high levels of organic enrichment. Physical disturbance subdued the effects of high levels of nutrient enrichment. The meio-macrobenthic comparison has been extended to other studies where both meiofaunal and macrofaunal responses have been determined. The response of meiobenthos is often, but not always, the same as that of macrobenthos. These inconsistencies can probably be explained by the constraints of the experimental design of the mesocosm, where macrobenthic recruitment is not possible, as well as the different ecology of these two faunal groups.