Carbon Stock Density of the Different Carbon Pools in Tulu Lafto Forest and Woodland Complex: Horo Guduru Wollega Zone, Oromia Region, Ethiopia

Abstract

Forest contains one of the world’s largest terrestrial C pools and play vital role in combating climate change through carbon sequestration. This study was conducted on Tulu Lafto Forest and woodland complex (here after named as TLF) with the objective of investigating carbon stock density of the different carbon pools and its variation between vegetation units. Data were collected from a total of 75 nested plots. Diameter at breast height and total height were measured for all woody individuals (trees, shrubs and lianas) that attained a DBH of 2.5 cm and above. Woody plants that did not attained a DBH of 2.5 cm and herbaceous plants were destructively harvested from subplots of 1 m2 within the main plot. All dead woods were also measured for their length and diameter and samples were taken to determine its specific wood density and decomposition class. Above and below ground biomass was estimated using allometric equation, while the litter carbon was determined by loss on ignition (LOI) method. Soil samples were also collected in order to determine soil organic carbon. The mean above and below ground C stocks were 218.4 and 43.49 t C ha-1, respectively while, C stocks in soil organic matter, dead wood and litter were 128.95, 6.15 and 2.43 t C ha-1, respectively. The total C stock density of TLF was found to be 399.42 ± 265.15 t C ha-1 of which 54.68 and 32.28% was kept in the aboveground biomass and soil, respectively. Result indicated that there is significant C stock density variation between vegetation units in the study area.