Carbon Stock Sequestered by Selected Tree Species Plantations in Wondo Genet College, Ethiopia

Climate change caused by global warming, is a phenomenon partly resulting from abundance of carbon dioxide in the atmosphere. Carbon sequestration through forestry plantations has a potential in ameliorating global environmental problems such as atmospheric accumulation of carbon dioxide and related climate change. The aim of this study was to estimate carbon sequestered by commonly grown plantation species across different ages. Four tree species were selected for the present study. Total 36 sample plots were selected for estimation of selected tree plantation biomass. Biomass data was collected at different age intervals (5-10 years, 11-15 years and ≥ 16 years) of tree plantation species. At each age interval of tree plantation three sample plots were selected for each species. A plot of 20 m × 20 m was established randomly in all study sites. Diameter at breast height (DBH) of each tree (≥ 10 cm) within 20 m × 20 m sample plot was measured by using caliper and height of each tree was measured by using hypsometer. The litter samples where be collected from the four corners and at the center with sub-sample of 1 m × 1 m in each sample plot. Soils were sampled in the same sub sample plots as litter. Aboveground and belowground biomass was estimated using specific species allometric equation. Aboveground carbon of Eucalyptus saligna, Cupressus lusitanica, Grevillea robusta and Pinus patula were sequestered (38.74, 39.05, 23.49 and 7.27 t/ha) respectively. Below ground carbon content of Eucalyptus saligna, Cupressus lusitanica, Grevillea robusta and Pinus patula (10.07, 10.15, 6.11 and 1.89 t/ ha) respectively. According to this study Eucalyptus saligna (0.006 t/ha), Cupressus lusitanica (0.007 t/ha), Pinus patula (0.006 t/ha) and Grevillea robusta (0.006 t/ha) were sequestered comparable litter carbon content. The study showed that Eucalyptus saligna (10.85 t/ha), Cupressus lusitanica (10.87 t/ha), Pinus patula (10.67 t/ha) and Grevillea robusta (11.36 t/ha) were storage similar soil organic carbon. According to this study the total carbon content of Grevillea robusta was 40.98, Eucalyptus saligna 59.68, Pinus patula 19.83 and Cupressus lusitanica 60.08 t/ha. Eucalyptus saligna and Cupressus lusitanica were sequestered high carbon, followed by Grevillea robusta and Pinus patula respectively.