The effect of pests and pathogens on forest harvesting regimes: A bioeconomic model
The effect of pests and pathogens on forest harvesting regimes: A bioeconomic model
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DOI：
10.1016/j.ecolecon.2023.107800
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发表时间：
2023-03-31
影响因子：
7
通讯作者：
Kleczkowski, Adam
中科院分区：
文献类型：
--
作者：
McTaggart, Ewan;Megiddo, Itamar;Kleczkowski, Adam
害虫和疾病对森林和林地中的树木构成了生存威胁。因此，迫切需要利用生态和生物经济模式，向森林管理人员提供关于控制和缓解战略的信息。例如，自20世纪90年代以来，英国的Dothistroma针叶枯萎病的发病率迅速增加，这对商业林业的生产力构成了重大威胁。预计气候变化将进一步加剧这一问题。在英国，对该病的控制主要侧重于通过商业前间伐进行良好的林分管理;类似的做法在世界各地的商业林中广泛使用。森林管理人员将受益于这一预防性战略（与其替代办法相比）在减少疾病影响和增加木材价值方面的有效性的证据。在本文中，我们开发了一个生物经济学模型，以确定经济上最优的收获制度-在间伐和轮换方面-一个均匀的年龄种植园下的入侵害虫的风险。我们扩展了Schaefer-Faustmann模型，包括一个房室流行病学系统，管理木材的生长和疾病的传播。我们分析了一套管理制度，包括时间的最后清除砍伐的森林和时间和水平的早期间伐。因此，在我们的方法中，森林管理者决定是否以及何时进行间伐，并且必须平衡（i）在感染破坏木材价值之前进行采伐和（ii）利用森林的密度依赖性增长。我们使用的敏感性分析，就疾病的传播和对树木动态的影响，以证明，在疾病的存在下，间伐可以显着提高净现值的种植园，如果应用正确。此外，如果间伐大大降低了传输速率，则优先考虑保护最终收获，并且在间伐时间缩短的同时延长轮作。我们的研究提供了一个框架，以帮助设计适当的森林管理策略，在疾病的存在。
Pests and diseases are an existential threat to trees in forests and woodlands. There is, therefore, a pressing need to use ecological and bioeconomic models to inform forest managers on control and mitigation strategies. For example, the incidence of Dothistroma needle blight in the UK has increased rapidly since the 1990s, and it is a significant threat to the productivity of commercial forestry. Climatic changes are expected to exacerbate this problem further. Control of the disease in the UK primarily focuses on good stand management through pre-commercial thinning; similar practices are widely used in commercial forests worldwide. Forest managers would benefit from evidence on the effectiveness of this precautionary strategy (in comparison to its alternatives) to reduce disease impacts and increase the value extracted from timber. In this paper, we develop a bioeconomic model to determine the economically optimal harvesting regime - in terms of thinning and rotation - of an even-aged plantation under the risk of an invading pest. We extend a Schaefer-Faustmann model to include a compartmental epidemiological system that governs timber growth and disease spread. We analyse a set of management regimes, including the timing of the final clear-felling of the forest and the timing and level of earlier thinning. Thus, in our approach, forest managers decide whether and when to thin and must balance (i) harvesting before infection destroys the timber's value and (ii) exploiting the forest's density-dependent growth. We use a sensitivity analysis with respect to the disease spread and impact on the tree dynamics to demonstrate that, in the presence of disease, thinning can significantly improve the net present value of the plantation if applied correctly. Furthermore, if thinning reduces the transmission rate significantly, the priority is to protect the final harvest, and rotations extend while the thinning time shortens. Our study provides a framework to help design appropriate forest management strategies in the presence of disease.