Carbon stocks of agroforestry systems in the Sudano-Sahelian zone of Cameroon, Central Africa Description of the subject

Abstract

Agroforestry systems (AFS) on the periphery of highly anthropized protected areas appear to be the most suitable production systems for providing a multitude of ecosystem services while reducing pressure on natural resources. They are indeed important carbon sinks whose compensatory role in the climate change mitigation process remains little known. Objectives. To assess the carbon storage potential of AFS in the peripheral zone of Bouba Ndjidda National Park as well as the financial value of these carbon stocks. Method. Data were collected in four types of AFS, namely sparse plantations (PE), hedgerows (HV), home gardens (JC), and fallows (JA). A total inventory of woody species was conducted and dendrometric data collected in 37 plots of 50 m x 50 m (8.5 ha). The pools considered for carbon stock assessment were woody aboveground biomass, belowground biomass, herbaceous biomass, litter and soil. Woody biomass was evaluated by allometric equations. Statistical analyses consisted of multiple comparison tests between the carbon stocks of the different AFS pools on the one hand and those of the AFS among themselves on the other hand. Results. Total carbon stocks ranged from 26.9 t C.ha-1 for fallows (JA) to 31.9 t C.ha- for hedgerows (HV). Average soil carbon stocks represented 31-59% of total carbon and decreased significantly with soil depth. In terms of payments for ecosystem services, prices for AFS carbon stocks were estimated to be between USD 986 and USD 1,170.ha-1. Conclusions. Agroforestry systems in the Sudano-Sahelian region play an important ecological and financial role by contributing significantly to the fight against climate change through carbon storage.