This study was conducted in the Cocoa Agro-Forests (CAF) of Mengomo’s locality. The aim was toevaluate the influence of some factors on carbon stocks. The sampling was done in 30 plots of 25 x 25 m2 in which all trees with a dbh≥10 cm were inventoried. The Shannon, Simpson and Evernnessindexeswere calculated to characterize the diversity of trees associated with cocoa. 62 species belonging to 48genera and 27 families were identified, the Anacardiaceae, Moraceae, Caesalpiniaceae, Mimosaceaeand Rutaceae, were revealed the most diverse families, with 5 species each. Shannon’s (3.66),Evernness’s (0.76) and Simpson’s (0.96) indexes have reflected a low diversity, dominated by some fewspecies. The average density of cocoa trees is 1028 trees/ha. They store about 22.51±5.86 Mg C/ha.Associated trees stored 124.20±60.05Mg C/ha for tree density of 113 trees/ha. These CAF sequesteredabout 146.71Mg C/ha. The multiple correspondence analyses showed that carbon stocks in the CAF arepositively correlated with the associated trees and the age of the CAF and negatively correlated with theabundance of cocoa trees. The biomass of cocoa is independent of the associated trees, but is inverselyrelated to the density of the associated trees.

This paper evaluates the potential effects of farmers’ species preferences on carbon stock in cocoa-based agroforestry systems (CAFS) in the Central Region of Cameroon. To achieve this goal, the species composition and structural variables of two land-use systems were investigated using 26 plots of 30 m × 30 m each, of which 20 were distributed in CAFS and 6 in adjacent secondary forests. Allometric models were used to estimate the species aboveground and root carbon stock. Ordination analysis indicated three types of species management systems: high-density timber and fruit trees; high-density Musaceae, palms and other shading trees; and low-density timber and fruit trees. The average densities of cocoa shading trees and shrubs were 234 ± 136 and 843 ± 360 individuals’ ha⁻¹, respectively. Thus, the average potential carbon stock of the sampled CAFS was estimated at 186.97 ± 86.06 Mg C ha⁻¹, 22% representing the root carbon stock. The transformation of secondary forest into various species management systems decreased the aboveground carbon by 18–34%. The annual rate of carbon accumulation estimated based on ring analyses was within the range 2.32–13.74 Mg C ha⁻¹ year⁻¹. The monetary value of the total carbon stored and the carbon accumulation rate were US$4042 ha⁻¹and US$159 ha⁻¹year^−1, respectively.

Forest stratification plays a crucial role in the interception of light and plants' photosynthetic activities. However, there is still a lack of information on the contribution of tropical forest stratification to its functioning, despite the increasing number of studies. Here, we analysed from a perspective of the whole tree community (WTC) and forest strata (i.e., large trees, understory trees, and small stems), the relationship between abiotic, biotic factors and aboveground Carbon (AGC). The abiotic factors‐AGC relationships were positive for all strata and WTC. However, soil factors‐AGC relationship was stronger for small stems and understorey, while topography factor‐AGC relationship was stronger for large trees and WTC. Tree size inequality‐AGC relationship was positive and much stronger for WTC, large trees and small stems. In addition, a species diversity‐AGC relationship was found positive only for large trees and WTC. These results highlight the niche complementarity effect for driving positive relationships of species diversity and individual tree size variation with aboveground biomass at large tree strata and WTC. The lack of positive effect of species diversity on AGC for understorey and small stems strata might be attributable to the selection effect or resource complementarity among species.