Floristic diversity and carbon stock in the Agrosystem of Persea americana Mill (Lauraceae) in the high Guinean savannahs of the Adamawa Cameroon

The knowledge on the floristic diversity of Persea americana agrosystem and their contribution to carbon stock was evaluated in the high-Guinean savannahs of Adamawa Cameroon. Three sites of different ages were identified according to the age of plantation. The savannah zone was chosen as the witness treatment. Sampling was done along five transects of 20 x 100m2 installed in each site giving a total of 20 transects. An inventory of shrubs with dbh ≥ 5 cm was carried out. The average estimates aboveground and belowground carbon stock in shrub biomass was calculated using the algometric equation. A total of 3296 individuals from 30 families, 53 genus and 61 species were counted. Comparative analysis was carried out to show that abundance, Shannon index and land area were significantly different in the different plots. Contrarily, Piélou equitability and ecology importance index do not vary much between pear trees and savannah. The total carbon stocks were estimated at 4.57t/ha (savannah) to 18.76 t/ha (others sites). Carbon sequestration ecological service value in the agrosystems was estimated to be more than 7126.6 dollars/ha with a liberation potential of about 712.66±2.11 tCO2/ha. These data show the capacity of the agrosystem of Persea americana to sequestrate more carbon compared to savannah vegetation that is subjected to constant disturbance by anthropic activities. Ecological services related to carbon can be an opportunity for financial benefits if the credits from the development of mechanism improves incomes of rural populations who contribute in the management and the conservation of the ecosystem.