I am carrying out a review of all the isotope fractionation processes in forest ecosystems. The idea is to be able to create a map of the ecosystem and place all fractionation processes, their direction (to the lighter or the heavier isotope) and their intensity. The scope of this project is to build a numerical model which will help understand isotope cycling in forest ecosystems. I am therefore looking for any references you may know of and I am also looking for contacts with which I could discuss.