ABSTRACT

Salvage logging of nematode-infested pinewoods could increase in South Korea, because of the risk of pest spread in response to climate change. No previous studies have precisely determined how to extrapolate information regarding cable extraction productivity and cost in salvage logging operations to steep terrains in South Korea. Therefore, in this study, the performance of a semi-mechanized system was observed at two different harvesting sites located in areas affected by the pinewood nematode (Bursaphelenchus xylophilus). The following were the specific aims of this study: (1) to evaluate HAM200 yarder productivity and cost in four different conditions (50 and 100 m yarding distances in uphill and downhill directions), and (2) to identify significant independent variables related to productivity. The HAM200 productivity values varied considerably and ranged from 1.95 to 2.52 m³/productive machine-hour (costs 43.29–55.81 US $/m³, respectively). Overall, productivity for trees damaged by uphill yarding was 20% higher compared to downhill yarding while productivity was not significantly different. Yarding direction, lateral distance, volume per cycle, and interaction of volume per cycle with lateral distance significantly affected the productivity. Further, our regression model, uphill yarding should be favorable from 35 to 100 m yarding distances. The findings of this study would enable better planning and decision-making regarding salvage logging, thereby allowing improved production of damaged trees.

摘要

由于害虫因气候变化而传播的风险，韩国对受线虫侵染的松木的补救采伐可能会增加。之前的研究没有准确确定如何将有关电缆提取效率和成本的信息外推到韩国陡峭地形的救助伐木作业中。因此，在本研究中，在受松材线虫 ( Bursaphelenchus xylophilus)影响的地区的两个不同采伐地点观察了半机械化系统的性能。）。本研究的具体目标如下：(1) 评估 HAM200 码垛机在四种不同条件下的生产率和成本（上坡和下坡的码垛距离为 50 和 100 m），以及 (2) 确定与生产率相关的重要独立变量. HAM200 生产率值变化很大，范围从 1.95 到 2.52 m ³ /生产机器小时（成本 43.29-55.81 美元/m ³， 分别）。总体而言，与下坡堆场相比，上坡堆场损坏的树木的生产力高出 20%，而生产力没有显着差异。码放方向、横向距离、每个周期的体积以及每个周期的体积与横向距离的相互作用显着影响了生产率。此外，我们的回归模型，从 35 到 100 m 的码距距离上坡码料应该是有利的。这项研究的结果将有助于更好地规划和决策打捞伐木，从而改善受损树木的生产。