Objective To evaluate the effect of parameter setting on the target solution quality of forest spatial planning via simulated annealing algorithm.

Method The tested parameters included the number of initial solutions (N), the number of iterations per new temperature (nrep), initial temperature (T) and cooling rate (r). The planning target was formulated to make timber production maximum over ten 5-year-planning periods, which should subject to the even-flow of harvest volume and area restriction model. The simulation datasets included five hypothetical datasets, which encompassed 3 300-81 600 binary decision variables.

Result The results showed that the coefficients of variation of objective function values for all the planning alternatives only varied from 0.18% to 14.95%, indicating the distinguished stability of simulated annealing algorithm. Parameters nrep and T can be estimated with the number of forests using polynomial (R²=0.85) and exponential (R²=0.66) functions respectively, however, the parameter r can be estimated with the reciprocal of the number of forests using polynomial function (R²=0.98). The values of parameter N was not related to the number of forests, but it should be somewhat above 500 times. Meanwhile, we also found that the number of units across a forest landscape not only affected the optimal values of each parameter, but also had significant effects on the probability of locating satisfactory solutions (PN) and resolution efficiency (RE) of simulated annealing algorithm, in which the PN increased linearly with the increase of number of units within a forest landscape (R²=0.98), but the RE presented a typical linear downtrend for the analytical datasets (R²=0.55).

Conclusion It is concluded that the quality of solutions of simulated annealing algorithm is sensitive to the parameters used and the size of planning options. In order to ensure the stability and quality of planning outputs, forest managers should determine the appropriate values of parameters of simulated annealing algorithm carefully when applied it to make forest planning in practice.