The objective of my study is to evaluate, over one year, the rate of mycorrhizal infection, the number of spores of mycorrhiza, and the nutrient content (C, N, P) of the soil microbial biomass (SMB) and to relate them to litter decomposition, litter quality, the stocks and flows of nutrients (C, N, P) in the soil of agroforestry systems (AFS) and secondary vegetation (capoeira) of the same age, at the depths of 0-10 cm and 20-30 cm of the soil profile. This objective stimulated the following questions:

1. Which system stocks larger dry mass of litter on the soil surface?
2. What is the polyphenol content on the litter of the system?
3. Which system has a larger stock of nutrients (C, N P) in SMB?
4. Do differences exist in SMB and in the rate of mycorrhizal infection at the depths of 0-10 cm and 20-30 cm of the soil profile?
5. Does some relationship exist between the P content of SMB and inorganic P of the soil?
6. Does some relationship exist between the rate of mycorrhizal infection and the number of mycorrhizal spores?
7. What is the influence of the fine roots of cupuaçu (Theobroma grandiflorum (S) K. Schumg)on litter decomposition?
8. What is the relationship between the dry mass of cupuaçu fine roots and the nutrient (N, P, K, Ca, Mg) and polyphenol concentration of the litter?

When I finish my studies and I can answer these subjects I hope to contribute to the knowledge on the flows and stocks of nutrients of central Amazonia, recuperation of degradated lands, and also to support the small local farmer, showing a form of use of the soil without damage to the environment.