Research has shown that the geological storage of CO2 has the potential to be an effective and safe way to rapidly reduce anthropogenic CO2 emissions. However, many stakeholders require the scientific community to demonstrate that all possible scenarios have been evaluated including the potential impacts of leakages into the biosphere. Several studies have examined the effects of naturally occurring CO2 on ecosystems. It is likely that these ecosystems will have been exposed to elevated CO2 for considerable periods and so species may have adapted. Thus the results may not be representative of the effects of possible leakage from a storage facility. However, preliminary work at the ASGARD (Artificial Soil Gassing and Response Detection) field site at the University of Nottingham has allowed some impacts of a controlled injection of CO2 on a non-adapted ecosystem and on soil chemistry to be assessed with changes observed in soil microbiology, soil geochemistry and the range and health of plants growing at the surface.