Analysis of carbon stock density in protected and non- protected areas of Guinea Savanna in Niger State, Nigeria

Abstract

Quantification of carbon stock has gained major attention in international climate change mitigation and adaptation negotiations. However, poor knowledge of the quantity of carbon stock in respective ecosystems is one major challenge in estimating carbon stock in developing countries. This study is aimed at estimating and comparing carbon stock density of protected (forest reserve) and non-protected (parkland) areas of guinea savanna in Niger state. The research methodology includes field survey inventory, biometric measurements and laboratory analysis. At each of the 45 sampling plot locations, Carbon stock was measured from six pools viz above ground tree, undergrowth, dead wood, litter, root and soil. within a quadrat sampling plot of 500 m 2 . Four fixed size square frames encompassing 1m 2 was used for the undergrowth (shrubs and grasses) and litter. Composite soil samples (for organic carbon) and undisturbed samples (for bulk density) were taken from each of the 1m 2 subplot quadrants at two depths (0-15cm and 15-30cm). Soil organic carbon concentration was estimated in the laboratory using Walkley-Black method. The findings of the study revealed that in terms of carbon stock in respective pools, in both protected and non-protected areas, soil pool was the highest, followed by tree and undergrowth; while litter, dead wood and root were the least in carbon stock. The average aggregate carbon stock density in the protected area is 118.2 Mg ha -1 which is greater than 69.3 Mg ha -1 recorded in the nonprotected area. It was also observed that there is significant difference in carbon stock density between the forest reserve and parkland study sites where t (43) = 18.34, p < 0.001). The study concludes that if savannas were to be protected from fire, grazing and anthropogenic disturbances, most of them would accumulate substantial carbon and the sink would be larger; with a view to mitigating climate change effect.