ABSTRACT To overcome existing knowledge gaps regarding altering harvest activities in the mixed species and heavily forested USA state of Maine, we used continuous forest inventory data to develop statistical models that predict harvest probability of occurrence and intensity. Among the three modeling approaches examined, the first one directly predicted stand-level basal area removal as a percentage of initial total stand basal area. The second approach first predicted stand-level harvest probability and then the stand-level basal area removal of the harvested plots only. The third approach used the stand-level harvest probability equation of the second approach, while subsequently predicting individual tree harvest probability for only the harvested plots. Among the most influential stand-level attributes were quadratic mean diameter, stand density, elevation, and ownership type, while the most influential tree-level attributes were diameter at breast height, basal area in larger trees, and species. Differences in prediction accuracy between modeling approaches were small with the third approach performing slightly better. Our findings suggest that harvesting in Maine might be less opportunistic and short-term driven than generally perceived. Overall, the analysis highlights the complex array of factors that influence harvesting patterns and provides a framework for better representing contrasting harvest behavior in future wood supply projections.

中文翻译：

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开发和比较各种林分和树木级建模方法，以预测美国东北部缅因州混交林的采伐发生率和强度

摘要 为了克服现有的关于改变混合物种和美国缅因州森林茂密的采伐活动的知识差距，我们使用连续的森林清查数据来开发统计模型，预测采伐发生的概率和强度。在研究的三种建模方法中，第一种直接预测林分基础面积去除占初始总林分基础面积的百分比。第二种方法首先预测林分级别的收获概率，然后仅预测已收获地块的林分级别基础面积去除。第三种方法使用第二种方法的林分收获概率方程，同时仅预测收获地块的单个树木收获概率。最有影响力的站级属性是二次平均直径、林分密度、海拔和所有权类型，而最有影响的树级属性是胸高直径、较大树木的基面积和物种。建模方法之间的预测精度差异很小，第三种方法的性能稍好一些。我们的研究结果表明，缅因州的收获可能不像人们普遍认为的那样机会主义和短期驱动。总体而言，该分析突出了影响采伐模式的一系列复杂因素，并提供了一个框架，以更好地代表未来木材供应预测中对比性的采伐行为。建模方法之间的预测精度差异很小，第三种方法的性能稍好一些。我们的研究结果表明，缅因州的收获可能不像人们普遍认为的那样机会主义和短期驱动。总体而言，该分析突出了影响采伐模式的一系列复杂因素，并提供了一个框架，以更好地代表未来木材供应预测中对比性的采伐行为。建模方法之间的预测精度差异很小，第三种方法的性能稍好一些。我们的研究结果表明，缅因州的收获可能不像人们普遍认为的那样机会主义和短期驱动。总体而言，该分析突出了影响采伐模式的一系列复杂因素，并提供了一个框架，以更好地代表未来木材供应预测中对比性的采伐行为。