Tree biomass and soil organic carbon densities across the Sudanese woodland savannah: A regional carbon sequestration study

Mean tree biomass and soil carbon (C) densities for 39 map sheet grids (1 degrees lat. x 1.5 degrees long.) covering the Acacia woodland savannah region of Sudan (10-16 degrees N; 21-36 degrees E) are presented. Data from the National Forest Inventory of Sudan, Harmonized World Soil Database and FAO Local Climate Estimator were used to calculate C densities, mean annual precipitation (MAP) and mean annual temperature (MAT). Above-ground biomass C and soil organic carbon (SOC. 1 m) densities averaged 112 and 5453 g C m(-2), respectively. Below-ground biomass C densities, estimated using root shoot ratios, averaged 33 g C m(-2). Biomass C densities and MAP increased southwards across the region while SOC densities were lowest in the centre of the region and increased westwards and eastwards. Both above-ground biomass C and SOC densities were significantly (p < 0.05) correlated with MAP (r(s) = 0.84 and r(s) = 0.34, respectively) but showed non-significant correlations with MAT (r(s) = -0.22 and r(s) = 0.24, respectively). SOC densities were significantly correlated with biomass C densities (r(s) = 0.34). The results indicated substantial under stocking of trees and depletion of SOC, and potential for C sequestration. Up-to-date regional and integrated soil and forest inventories are required for planning improved land-use management and restoration. (C) 2012 Elsevier Ltd. All rights reserved.