Macpherson Morag F, Kleczkowski Adam, Healey John R, Hanley Nick
1Computing Science and Mathematics, School of Natural Sciences, Cottrell Building, University of Stirling, Stirling, FK9 4LA UK.
2School of Environment, Natural Resources and Geography, College of Natural Sciences, Bangor University, Gwynedd, Bangor, LL57 2UW UK.
Environ Resour Econ (Dordr). 2018;70(3):565-588. doi: 10.1007/s10640-016-0077-4. Epub 2016 Oct 27.
The arrival of novel pathogens and pests can have a devastating effect on the market values of forests. Calibrating management strategies/decisions to consider the effect of disease may help to reduce disease impacts on forests. Here, we use a novel generalisable, bioeconomic model framework, which combines an epidemiological compartmental model with a Faustmann optimal rotation length model, to explore the management decision of when to harvest a single rotation, even-aged, plantation forest under varying disease conditions. Sensitivity analysis of the rate of spread of infection and the effect of disease on the timber value reveals a key trade-off between waiting for the timber to grow and the infection spreading further. We show that the optimal rotation length, which maximises the net present value of the forest, is reduced when timber from infected trees has no value; but when the infection spreads quickly, and the value of timber from infected trees is non-zero, it can be optimal to wait until the disease-free optimal rotation length to harvest. Our original approach provides an exemplar framework showing how a bioeconomic model can be used to examine the effect of tree diseases on management strategies/decisions.
新病原体和害虫的出现可能会对森林的市场价值产生毁灭性影响。调整管理策略/决策以考虑疾病的影响，可能有助于减少疾病对森林的影响。在此，我们使用一种新颖的、可推广的生物经济模型框架，该框架将流行病学 compartments 模型与 Faustmann 最优轮伐期模型相结合，以探讨在不同疾病条件下，何时采伐单一轮伐期、同龄人工林的管理决策。对感染传播速率和疾病对木材价值的影响进行敏感性分析，揭示了在等待木材生长与感染进一步扩散之间的关键权衡。我们表明，当受感染树木的木材没有价值时，使森林净现值最大化的最优轮伐期会缩短；但当感染迅速传播且受感染树木的木材价值非零时，等到无病的最优轮伐期再进行采伐可能是最优的。我们的原始方法提供了一个示例框架，展示了如何使用生物经济模型来研究树木疾病对管理策略/决策的影响。
