Impacts of forest management intensity on carbon accumulation of China's forest plantations

Characterized by young age and a large area been newly planted, China's forests were projected to have high carbon (C) uptake potential in the future. While such a potential assumes continuous human management, the effects of forest management on C uptake potential are less clear. Using surveyed data collected from a recent nationwide field campaign conducted between 2011 and 2015, we examined human management effects on C stock dynamics in three of the most widely planted forests in southern China, i.e. Pinus massoniana, Cunninghamia lanceolate, and Eucalyptus. Vegetation C accumulation rates were larger under higher management intensities in Pinus massoniana and Eucalyptus, while there was no such a pattern in Cunninghamia lanceolate. Human management has contributed to vegetation C increment by 2.42 Tg C yr(-1) and 0.55 Tg C yr(-1) in Pinus and Cunninghamia forests. While in comparison, human management impacts on C accumulation were not accountable in Eucalyptus due to lack of naturally regenerated forests. Moreover, we found that potential vegetation C accumulation can be enhanced by 7.86 Tg C yr(-1) from higher management intensity with 3.86, 2.17, and 1.83 Tg C yr(-1) from Pinus massoniana, Cunninghamia lanceolate, and Eucalyptus, respectively. We also advise that different management intensities should be considered to avoid biases for projection of future C sink from forest plantations regionally or nationally.