Agroforestry systems (SAFs) constitute an important agricultural practice of land use directed at food production and environmental services. The objective of this study was to evaluate carbon stock and cycling of 4 agroforestry systems (SAF) with different age and species composition, and a secondary vegetation (“capoeira”), in Tomé-Acu, northeast of Pará State, Eastern Amazon. Carbon stocks in soil, litter and aboveground biomass were measured. Carbon flux associated with litterfall and aboveground biomass increment was measured over a year between 2008 and 2009. The SAFs were divided into four categories, called SAF 1, SAF 2, SAF 3 and SAF 4, being (SAF 1: cacau, açaí, bananeira e seringueira, 14 years old, SAF 2: cacau, açaí, bananeira, seringueira, taperebá, paricá e macacaúba, 14 years old, SAF 3: cupuaçu, açaí, teca e mogno, 9 years old, SAF 4:cupuaçu, açaí e paricá, 9 anos years old). In each system we set four plots, where soil and plant samples were collected, including diameter at breast height (DAP) and height (h), which were used to estimate the aboveground biomass. Within plots were installed collectors to measure the deposition of litterfall and sampled soil and litter used to estimate carbon stocks. There was no significant difference between SAFs in relation to soil carbon stock. The SAF 3 was significantly lower than the other SAF in relation to aboveground carbon and SAF 4 had the highest annual litterfall deposition among all treatments. The SAF did not differ in relation to soil and litter carbon stocks. Net primary production reached 2.54, 6.11, 9.54 and 16.27 Mg C ha-1 yr-1 in SAF 1, 2, 3 and 4, respectively. The age of the SAFs had no significant effect on the amount of carbon accumulated during one year.
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