Terrestrial isopods largely influence the process of decomposition via fragmentation and comminution of leaf litter. Trachelipus rathkei is a terrestrial isopod that is not native but commonly found in forested ecosystems of northern Wisconsin. This study investigated the performance of Trachelipus rathkei on birch and aspen leaf litter produced under elevated CO₂ and/or elevated O₃ conditions.

Results/Conclusions

The relative consumption rate of isopods was higher when given birch than aspen litter. When provided litter produced under elevated CO_2, relative consumption rate decreased, regardless of litter type. When provided litter produced under elevated O₃, relative consumption rate increased on birch and decreased on aspen litter. Relative growth rates of isopods did not significantly change in response to litter species or fumigation treatment. Changes in consumption rates of litter macrofauna, such as terrestrial isopods, may alter decomposition and therefore nutrient turnover in forested ecosystems under atmospheric conditions of the future.