Carbon sequestration in the soils of Northern Ireland: potential based on mineralogical controls

Complex relationships between soil organic carbon (SOC), mineralogy, land-use and climate may exist in the soils of Northern Ireland. Greater understanding of these interactions can improve the effectiveness of SOC sequestration and management strategies. Mineralogy and SOC concentrations in soils derived from four different parent rocks (sandstone, shale, basalt and granodiorite) were characterised and indicate that soil mineralogy and geochemistry play an important role in determining the concentration of SOC. This primarily depended on the absence or presence of high surface area clay and iron oxide minerals and on the soil pH. Soil mineralogy did not appear to have a major impact on the composition of soil organic matter (SOM) with depth. The results suggest that when carbon sequestration practices in Northern Ireland are considered, soils derived from basalts are likely to acquire greater carbon concentrations than soils from other lithologies