Abstract: Non-traditional stable isotopes have been widely applied to the studies on the Earths surface environment during the last ten years. In the critical zone, soils continuously exchange materials and energy with the atmosphere and lithosphere with the aid of water and biota. A brief review was presented of the fractionation and potential applications of non-traditional stable isotope in soil studies. Taking Mg, Fe, Si and Hg isotope systematics as examples, a few important scientific problems of soil research were discussed, including weathering and pedogenesis, the cycle of nutrient elements between plants and soils, and heavy metal pollution. The current progresses of non-traditional stable isotopes in soil research was briefly reviewed and future directions in this field were outlined. The application of non-traditional stable isotopes in soil is a nice example of the multi-disciplinary studies combining stable isotope geochemistry, soil science, and environmental ecology.

Key words: soil, non-traditional stable isotope, isotopic fractionation, weathering and pedogenesis, plant, heavy metal pollution