Coupling and Long-term Change Characteristics of Forest Carbon Sink and Forestry Economic Development in China

[Objectives] To analyze the changes in of forest carbon sink and forestry economic development, provide reference for relevant management decisions, ecological governance and resource and environment management, and promote the development of green low-carbon economy in China. [Methods] Based on the data of six forest resource inventories from 1989 to 2018 and related studies, the comprehensive evaluation model of forest carbon sink and forestry economic development, the coupling degree model of forest carbon sink and forestry economic development, and the coupling coordination degree model of forest carbon sink and forestry economic development were adopted. The coupling degree of forest carbon sink and forestry economic development from 1992 to 2018 was analyzed. Stepwise regression and ARIMA model were used to analyze the influencing factors and lagging characteristics of forest carbon sink. The coupling degree between forest carbon sink and forestry economic development in China from 2019 to 2030 was predicted by autoregression and ADF test. The coupling between forest carbon sink and forestry economic development in China and its long-term change characteristics were also discussed in this study. [Results] (i) The investment of ecological construction and protection, the actual investment of forestry key ecological projects, GDP and the import of forest products had a significant impact on forest resources carbon stock. The total output value of forestry industry, the actually completed investment of forestry key ecological projects and the export volume of forest products had a significant impact on the forest carbon sink, and the actually completed investment of forestry key ecological projects has the greatest impact on the two. (ii) The impact of actually completed investment of forestry key ecological projects had a lag of 2 years on the forest resources carbon stock and a lag of 1 year on the forest carbon sink. When investing in forest carbon sink, it is necessary to make a good plan in advance, and do a good job in forest resources management and time optimization. (iii) From 1992 to 2018, the coupling degree of forest resources carbon stock, forest carbon sink and long-term development of forestry economy in China was gradually increasing. Although there were some fluctuations in the middle time, the coupling degree of forest resources carbon stock and the long-term development of forestry economy increased by 9.24% annually, and the degree of coupling coordination increased from "serious imbalance" in 1992 to "high-quality coordination" in 2018. From 1993 to 2018, the coupling degree of forest carbon sink and long-term development of forestry economy increased by 9.63% annually, slightly faster than the coupling coordination degree of forest resources carbon stock and long-term development of forestry economy. The coordination level also rose from level 2 in 1993 to level 10 in 2018. (iv) The prediction shows that the coupling coordination degree of forest resources carbon stock, forest carbon sink and the long-term development of forestry economy would increase from 2019 to 2030. The coupling coordination degree (D) values of both were close to 1, the coordination level was also 10 for a long time, and the degree of coupling coordination was also maintained at the "high-quality coordination" level for a long time. [Conclusions] Forest has multiple benefits of society, economy and ecology, and forest carbon sink is only a benefit output. The long-term coupling analysis of forest carbon sink and forestry economic development is a key point to multiple benefit analysis. The analysis shows that the spillover effect and co-evolution effect of forest carbon sink in China are significant. From 1992 to 2018, the coupling coordination degree of forest carbon sink and forestry economic development was gradually rising. The prediction analysis also indicate that the coupling coordination degree between the forest carbon sink and the long-term development of forestry economy will remain at the level of "high-quality coordination" for a long time from 2019 to 2030. Therefore, improving the level of forest management and maintaining the current trend of increasing forest resources are the key to achieving the goal of carbon peaking and carbon neutrality in China.