WOODY SPECIES DIVERSITY AND CARBON SEQUESTRATION POTENTIALS OF SALAYSH FOREST IN NORTH SHEWA, ETHIOPIA

ABSTRACT The study was conducted in Salaysh Forest in Abichu and Gnea District of North Shewa Zone of Oromia National Regional state, Ethiopia. The overall objective of this study was to investigate the woody species diversity and the carbon stock potential of the Salaysh Forest. Collection of vegetation data was made using systematic sampling methods in a total of 30 plots. Heights (>1.5m), diameters (>2.5cm) and numbers of woody species were recorded from each quadrant with 20 m x 20 m for trees and 5m x 5m for shrubs. In addition, 1 m x 1m sub-quadrants were laid within the main quadrant to sample litter biomass as well as soil sample. Soil was collected from two soil depth (0-15 and 15-30 cm) and analyzed at Debere Berhan soil laboratory research center. In the Salaysh forest, species evenness and species diversity of woody plants were calculated, above and below ground, dead wood and litter fall carbon stock's potential of woody species were estimated using allometric equations. Soil organic carbon was determined by using Walkley-Black method. The relation between woody species diversity and the carbon stock potential of the study area was test by correlation coefficient. A total of 17 woody species were identified belonging 14 families from Salaysh forest. The Shannon diversity index (H') and evenness value was 0.89 and 0.85, respectively. The mean AGC, BGC, LC, DWC and SOC were, 0.021t/ha, 0.0031t/ha, 6.1t/ha, 0.0033t/ha and 112.1t/ha, accumulated respectively. In the study site, 3545.76t/ha total carbon stocks was accumulated with an equivalent CO2 of 13012.92t/ha. Shannon diversity index and species evenness were not significant (p>0.05) positively correlated (r=0. 12 and 0.26), respectively, with AGBC. Shannon diversity index and species evenness were not significant (p>0.05) positively correlated (r=0.113 and 0.13), respectively, with BGBC. Shannon diversity index and species evenness were not significant (p>0.05) positively correlated (r=0.08 and 0.065) respectively, with LC. Shannon diversity index and species evenness were not significant (p>0.05) negatively correlated(r= -0.146 and -0.1739, respectively, with SOC. Woody species evenness and diversity had no significant relationship to biomass carbon stocks. Therefore, carbon stock enrichment was not as a result of species evenness or diversification of woody species.