Forest soils contain more carbon than the entire atmosphere and thus the exchange of carbon dioxide between forest soils and the atmosphere can influence the global carbon cycle and climate change. Changes taking place in forests today, including shifts in the identity of dominant tree species and exotic earthworm species invasions, threaten to perturb the carbon balance of these ecosystems. Unfortunately, the effect of these two disturbances on forest soil carbon storage is largely unknown. The intent of this proposal is to study the influence of tree species and earthworms on soil carbon storage at a unique field experiment in Poland, where 14 different tree species were planted more than 35 years ago. At this site, tree species are known to differ with respect to the earthworm populations they support and other qualities that could influence soil carbon, including leaf and fine root characteristics. The research put forth in this proposal will relate these known species differences to new studies of soil carbon dynamics using advanced molecular and isotopic analytical tools.
By defining clear relationships between tree species, earthworms, and soil carbon storage, the consequences of changing tree species composition and earthworm invasions on the carbon balance of forests can be better understood. This information could be used to manage the species composition of U.S. forests for the purpose of carbon sequestration, facilitating participation in economic and political pursuits aimed at carbon management and climate change mitigation.
