Evaluation and scenario simulation for forest ecological security in China

Continuously growing populations and rapid economic development have led to the excessive use of forest resources, and the forest ecosystem is threatened. In response, forest ecological security (FES) has attracted attention. In this study, an integrated dynamic simulation model was constructed using the system dynamic method, and it was used to evaluate the FES in China from 1999 to 2014. A scenario analysis was then used to evaluate the changes in the FES under five forestry policy scenarios for the 2015-2050 period, including the baseline, afforestation policy, harvesting policies, management policy, investment policy, and a policy mix. The results showed that the evaluation values of the FES increased during the period from 1999 to 2002, the period from 2004 to 2010 and the year 2014, and they decreased in 2003 and during the period from 2011 to 2013. During the 2015-2050 simulation period, the FES improved continuously. In particular, China would enter a new stage when the economic systems, social systems and ecosystems were in harmony after 2040. To improve the FES and the current status of the FES, a scenario analysis showed the most suitable scenario to be Scenario 5 from 2015 to 2020 and Scenario 2 from 2021 to 2050. To relieve pressure, the most suitable scenario would be Scenario 5 from 2015 to 2040 and from 2046 to 2050, and the most suitable scenario would be Scenario 4 for 2041-2045. A policy mix (Scenario 5) would be most efficient under current conditions, while the effects of all the benefits of the forestry policies would weaken over the long term. The integrated method can be regarded as a decision support tool to help policy makers understand FES and promulgate a reasonable forestry policy.