Carbon stocks in a 50-year-old Eucalyptus camaldulensis stand in Sicily, Italy

Abstract

Eucalyptus stands in semi-arid areas may contribute to enhance carbon (C) stocks in both biomass and soil. However, the limited information available is mainly focused on short-rotation plantations. In this study, the aboveand below-ground C pools in five 50-year-old Eucalyptus camaldulensis Dehnh. stands planted on Miocenic evaporitic deposits in Sicily, Italy, with a xeric and thermic pedoclimate, were measured. Above-ground biomass was determined by partitioning and weighing branches, stem and leaves. Below-ground C pools included the determination of litter, root biomass, and soil organic and inorganic C. In terms of the above-ground biomass, the E. camaldulensis stand accumulated on average 116 Mg ha⁻¹ corresponding to 55 Mg C ha⁻¹. Below-ground biomass consisted mainly of larger roots, followed by fine and medium roots (33 Mg ha⁻¹ corresponding to 14 Mg C ha⁻¹). Litter accumulation on the soil surface accounted for 13 Mg ha⁻¹ corresponding to 5 Mg C ha⁻¹. The amount of C stored in soil was 554 Mg C ha⁻¹, of which 75% was in organic form. Although E. camaldulensis is planted extensively throughout the Southern Hemisphere and tropics where it is managed over short rotations (c. 2–4 years), the results obtained from this study make this species important in terms of future afforestation planning for longer rotations due to its potential to sequester C, particularly in the below-ground components.

Keywords: above-ground biomass, below-ground biomass, evaporitic deposits, litter, roots, semi-arid Mediterranean climate, soil