Interactions between atmospheric CO2 enrichment and soil fauna

We have reviewed the responses of soil fauna to increased concentrations of atmospheric CO2 and the consequent climate change. These will affect sever al attributes of animal populations and communities including their density , biomass, diversity, activity, rates of consumption, life history paramete rs and migration ability. Changes in the quality and quantity of litter and global warming are the main factors which are expected to modify soil faun a. Although changes have been observed in several attributes of the soil fa una as a consequence of increased concentrations of atmospheric CO2, no gen eral trend which might allow to the prediction of a general pattern of resp onse has been identified. Because of the complexity of the biological mecha nisms and the synergetic action of several factors, the few resulting respo nses reported in the literature are inconclusive. However, some aspects of the situation deserve more attention. These include the consequences of (1) changes in the food resources for soil fauna in the litter layer and in th e rhizosphere, (2) the consumption of low quality litter by the macrofauna, (3) the change in life span in response to temperature elevation, (4) the enhancement of earthworm burrowing activity and (5) the changes in communit y composition arising because of specific differential resistance to advers e conditions.