Misalignment between ecologically rapid and economically optimal forest restoration designs

Because the benefits of forest restoration take a long time to materialize, it is desirable to design restoration projects with intergenerational equity in mind, particularly considering the perspectives and feelings of the generation bearing the costs. We conducted a contingent valuation survey with a payment card among the Japanese public focusing on forest restoration in Shiretoko National Park to estimate individual discount rates for carbon and biodiversity recovery. Specifically, we presented two forest restoration scenarios with varying recovery times and asked for their willingness to pay (WTP) for each. From these differences in WTP, the individual discount rates were estimated at 1.17 %. Using the estimated discount rates, cost-benefit analyses were performed on the simulation results of 31 different restoration scenarios with varying planting densities and number of species planted. We also performed the same analyses using commonly used discount rates of 4.0 % and 6.0 %. The results showed a divergence between the ecologically and economically optimal restoration scenarios, and that the economically optimal restoration scenario varied depending on the discount rate. This highlights the need for careful consensus building that combines ecological and economic perspectives in forest ecosystem management.