Critical ecosystem services and biodiversity are generally delivered more effectively by native forests than by tree plantations, according to a new global study assessing the merits of various reforestation approaches. The findings illustrate important trade-offs that need to be considered when meeting forest restoration commitments.
Forest restoration, particularly on degraded and deforested lands, is widely touted as a practical approach to mitigate climate change and its impacts. However, although many ambitious reforesting initiatives are underway, including the Bonn Challenge, which pledges to restore some 350 hectares of forest by 2030, a rigorous comparison of the contributions and trade-offs of different forest restoration approaches is lacking.
As a result, its assumed that key ecosystem services can be delivered by forests regardless of their composition, leading to programs that tend toward reforesting with extensive, compositionally simple tree plantations. To evaluate how core ecosystem services, including carbon storage, soil and water management, and biodiversity, compare across a range of tree plantations and restored native forests, Fangyuan Hua and colleagues devised a global synthesis of data from 264 studies in 53 countries and spanning the planet's major forest biomes.
Hua et al. show the native forests consistently deliver better services than plantations, particularly in warmer and drier regions where plantations performed most poorly. Where plantations did shine, however, was in providing greater wood production for harvest. According to the authors, the benefits of reforestation efforts are best achieved through the restoration of native forests and not through extensive tree plantations.
Source: https://www.aaas.org/