Reconstructing Long‐Term Forest Age of China by Combining Forest Inventories, Satellite‐Based Forest Age and Forest Cover Data Sets

Abstract

Forest age is one of the most important forest ecosystem characteristics which largely affects the biomass and carbon sink of forest ecosystems (Pugh et al., 2019;Zhu, 2020). It has been well established that the net primary production of forest increases with the stand age in young stands, then declines after the forest reaches its mature succession (Ryan et al., 1997;Zaehle et al., 2006) due to age-related changes in carbon allocation (Xia et al., 2019), hydraulic conductance (Woodruff & Meinzer, 2011) and nutrient supply (Van Cleve et al., 1991). A recent study emphasized that nearly half of the carbon sink (0.53 Pg C yr −1 ) in regrowth forest was due to changes in forest demography alone, which accounted for one-fourth of the global forest carbon sink between 2001(Pugh et al., 2019. Therefore, forest stand age has been an important variable in process-based ecosystem models or empirical models for simulating carbon cycle dynamics of forest ecosystems (

Factors driving carbon accumulation in forest biomass and soil organic carbon across natural forests and planted forests in China

“…Since 1998, China has been implementing comprehensive static logging practices in its natural forests, fostering forest restoration and ecological succession (Jing et al, 2021). However, in light of the predominant tree species in China's natural forests, many forests have now reached middle age (China State Forestry and Grassland Administration, 2019;Xia et al, 2023). Data show that the proportion of middle-aged natural forests is 36% (Supplementary Table 3).…”