Abstract:
Objective How to improve the carbon sink role of forests under the background of carbon neutrality and continue to increase forest carbon storage has become a focus of attention of all parties. Reasonable tree species mixture is the basis for improving forest quality and carbon sink capacity.
Method Based on the 15 years (2004−2019) consecutive data of four forest inventories in a 25 hectare dynamic sample plot of broadleaved Korean pine forest in Changbai Mountain of northeastern China, we analyzed the contribution of different tree species to aboveground biomass carbon storage, and compared the differences in carbon sequestration rates of different tree species as well as their interspecific asynchrony.
Result (1) The aboveground biomass of broadleaved Korean pine forest in the latest inventory was about (282.5 ± 102.8) Mg/ha, and the annual mean net carbon sequestration rate of aboveground biomass was about 1.0 Mg/ha in the past 15 years. The carbon sequestration rates among the three periods (2004−2009, 2009−2014, 2014−2019) were 1.54, 0.73 and 0.76 Mg/(ha·year), respectively. (2) The aboveground biomass of the seven dominant tree species accounted for about 96.2% of the total aboveground biomass of the entire community, and the three most important tree species (i.e., Tilia amurensis, Fraxinus mandshurica and Quercus mongolica) contributed 73.6% of the total aboveground biomass. (3) The population number of five tree species, including Tilia amurensis, Fraxinus mandshurica, Quercus mongolica, Pinus koraiensis and Ulmus japonica, continued to decline, while their average DBH and aboveground biomass showed a directional increasing trend. (4) The aboveground biomass carbon sequestration rate of the seven dominant tree species ranged from −0.97% to 0.77%, and Fraxinus mandshurica with compound leaf character had the fastest aboveground biomass accumulation rate (0.77%), followed by Tilia amurensis (0.60%), Ulmus japonica (0.54%), Quercus mongolica (0.38%), Pinus koraiensis (0.09%), Acer mono (−0.46%), Populus ussuriensis (−0.97%). (5) The seven most important populations showed different growth dynamics during three monitoring periods, and the relationships between Tilia amurensis and Acer mono, Quercus mongolica and Pinus koraiensis, Fraxinus mandshurica and Ulmus japonica showed a relative higher positive correlation relationship, whereas a negative relationship existed between Populus ussuriensis and Ulmus japonica.
Conclusion The temporal asynchrony of carbon sequestration rates among tree species could provide a certain reference for tree species selection and configuration in afforestation practice in this area.