Vegetation structure, carbon sequestration potential and species conservation in four agroforestry systems in Cameroon (Tropical Africa)

ABSTRACT As the rate of forest degradation continues to rise, agroforestry may serve as a way of conserving species and carbon sinks. The aim of this study was to assess agrobiodiversity and carbon sequestration potential in agrosystems in Cameroon. Three age groups of agrosystems were studied. Data were collected in 100x50 m2 quadrates. Density ranged from 53.17±0.08 to 1463±50.11; basal area from 2.07±0.00 to 988.39±16.13 m2/ha; Shannon diversity from 3.3±0.71 to 3.68±0.72; Carbon storage from 12.1±0.27 to 54.65±1.38 t C/ha for 1-10-year-old agrosystems with lowest values in neem; 34.78±0.87 to 71.34±1.6 t C/ha for 10-20-year-old stands with lowest values in cashew; 28.24±0.04 to 108.51±2.46 t C/ha for +20-year-old stands with highest values in eucalyptus; Carbon sequestration potential from 296.7±1.98 to 859.33±10.01 t CO2eq/ha. The highest carbon stocks were found in eucalyptus stands (p<0.05). Several endogenous species, especially Afzelia bipindensis (EN), Leptoderris ledermannii (EN), Mansonia altissima (EN), Entandrophragma cylindricum (VU), Nesogordonia papaverifera (VU), Quassia sanguinea (VU), Vitellaria paradoxa (VU), Afzelia africana (VU), Erythrina senegalensis (LC), Detarium microcarpum (LC), senna spectabilis (LC), were assessed. Other overexploited species, especially Carissa edulis, Zanthoxylum zanthoxyloides, Adansonia digitata, Securidaca longepedonculata, were assessed as well. The studied systems are significant CO2eq sinks and refuge centre for agrobiodiversity

Carbon storage in cashew plantations in Central Africa: case of Cameroon

This study aimed to assess the carbon storage in cashew plantations in the Sudano-Sahelian zone of Cameroon. Quantification of stocks of biomass and carbon dioxide contained in agroforestry systems has become an international priority within the framework of the implementation of REDD + mechanism. Three cashew plantations were selected according to age classes (0–10 years; 10–20 years and over 20 years) in the four subdivisions (Bénoué, Faro, Mayo-Louti and Mayo-Rey). The experimental device installed is a complete random Fisher block with five repetitions. A 100 m × 20 m transect method was undertaken to assess the biomass. Allometric equations were used to assess carbon stock in biomass and laboratory analysis was used to assess soil carbon stock. Carbon stocks varied following the subdivisions and ranged from 69.29 to 96.67; 62.24 to 82.61; 59.00 to 90.64 and 66.14 to 84.03 tC/ha respectively in Bénoué, Faro, Mayo-Louti and Mayo-Rey. Soil carbon stock varied following the subdivisions and ranged from 22.03 to 30.33; 20.12 to 25.43; 19.21 to 25.73 and 21.06 to 24.51 tC/ha respectively in Bénoué, Faro, Mayo-Louti and Mayo-Rey. The highest total carbon stock was recorded in Bénoué subdivision (81.85 ± 13.55 t C/ha). The cashew plantation is actively sequestering carbon showing the potentiality to mitigate global climate change. Finally, these results are also an important economic, ecological and dynamic informative value to serve as a basis for guiding any program of action aimed at the conservation and sustainable management of this species