Abstract

Increasing effects of climate change has led to an urgent need for reliable estimates of the soil carbon pool (SOC) which is one of the carbon sinks in the world. This is especially true in Africa where there is lack of basic data. This study conducted in the southern part of Mount Cameroon National Park (MCNP) seeks to determine SOC patterns and estimate CO₂ equivalence from SOC pool following land-use changes. Nine prominent land-use types were identified (under rubber, virgin forest reserve, oil palm, cassava, mixed cropping, tea, maize, banana and sugar cane). Soil samples were collected from 98 plots of 2,500 m², each spread over the different land uses in five villages at 0 - 30 cm of soil. The collected Soils samples were analyzed for SOC and other physicochemical properties. Mean SOC ranged from 56.1± 11.00 t ha-1  (for rubber) to 225.24 ± 33.65 t ha-1 ¹ (for forest) giving an average for the area of 130.80 Mg/ha. The mean SOC in forest soil was significantly higher than that for cassava (p=0.038), oil palm (p=0.045) and rubber (t=4.849, p=0.0046). Losses in CO₂ equivalence, as a result of land use change from forest to other land use systems, ranged from 234.15 (for mixed cropping) to 620.74 t/ha (for rubber). The study provided estimates of carbon pools for different land uses in MCNP. Mixed cropping was only second to forest in terms of SOC values indicating that agroforestry can mediate between food production and environmental protection.

Key words: Soil organic carbon, land use systems, CO_2, carbon sequestration, soil quality.