Preface; 1. Arctic soils and permafrost E. A. FitzPatrick; 2. Microbial ecology, decomposition and nutrient cycling C. H. Robinson and P. A. Wookey; 3. The role of bryophytes and lichens in polar ecosystems R. E. Longton; 4. The role of arctic vegetation in ecosystem and global processes F. S. Chaplin III, J. P. McFadden and S. E. Hobbie; 5. Habitat fragility as an aid to long-term survival in arctic vegetation R. M. M. Crawford; 6. Life strategies of arctic terrestrial arthropods J. S. Bale, I. D. Hodkinson, W. Block, N. R. Webb, S. C. Coulson and A. T. Strathdee; 7. Environmental fluctuations in arctic marine ecosystems as reflected by variablility in reproduction of polar bears and ringed seals I. Stirling and N. J. Lunn; 8. Trophic interactions in arctic ecosystems and the occurrence of a terrestrial trophic cascade D. R. Bazely and R. L. Jefferies; 9. Pathways and effects of contaminants in the Arctic E. Steinnes; 10. Effects of acid deposition on arctic vegetation S. J. Woodin; 11. Effects of enhanced UV-B radiation on subarctic vegetation L. O. Bjorn, T. V. Callaghan, C. Gehrke, D. Gwynn-Jones, B. Holmgren, U. Johanson and M. Sonesson; 12. Effects of CO2 and climate change on arctic ecosystems W. C. Oechel, A. C. Cook, S. J. Hastings and G. L. Vourlitis; Index.