The role of abandoned Short Rotation Forestry (SRF) plantations in plant carbon storage: a case study in Central Italy

AbstractAt the end of the last century, European Union (EU) energy policy encouraged the use of dedicated (Short Rotation Forestry or SRF) plantations in member countries in which fast-growing woody species are grown for energy purposes. Recently, in Italy some SRF plantations developed in the 90s have been abandoned or managed more extensively for economic and environmental reasons. However, these abandoned plantations can play a key role in biodiversity conservation and carbon storage. The present study is aimed to investigate the role of abandoned SRF plantations in climate change mitigation through the estimation of the plant carbon stock (C-stock) and fluxes (C-sequestration) in a case study in Central Italy. The C-stock and C-sequestration were estimated in three different 20-years SRF plantations (hybrid poplar, willow, black locust) located on the same site and unmanaged for 15 years. The results show a C-stock considering three of five C pools) equal to: 47.30 MgC ha− 1for hybrid poplar (65.3% in biomass and 34.7% in deadwood respectively), 23.02 MgC ha− 1for willow (77.6% and 22.4% respectively), and 80.41 MgC ha− 1for black locust (95.9% and 4.1% respectively). The average C-sequestration for the period 2008–2021 is estimated in 2.22 MgC ha− 1yr− 1for hybrid poplar, 1.91 MgC ha− 1yr− 1for willow, and 3.29 MgC ha− 1yr− 1for black locust plantations. Outcomes of the present research offer support for the forest restoration practices of similar abandoned SRF plantations. The application of extensive management techniques and the development of the naturalization process will ensure the role of “stepping stone” of these plantations, helping their evolution toward semi-natural systems mainly oriented to biodiversity conservation, habitats provision and C sink.