There is increasing evidence supporting rapid trajectories of environmental change in the Antarctic. This study describes preliminary data on soil faunal responses to artificial environmental amelioration obtained using a 'greenhouse' methodology, over the first year of a manipulative study of part of the soil ecosystem of Mars Oasis, Alexander Island in the southern Maritime Antarctic. The methodology, which used two types of UV-absorbing perspex cloche, influences a range of environmental variables, the most significant of which in this study are thought to be temperature and UV-radiation. The fauna of this site is dominated by Nematoda. Responses to amelioration included large increases in nematode population densities, particularly those of the microbivorous genus, Plectus, combined with changes in the relative abundance of taxa. These faunal changes are likely to be mediated via the responses of autotrophs to the environmental manipulations.