Impoving silvicultural systems for mixedwood forests through an evaluation of past, present and future stand responses- natural disturbance compared to harvesting

需要发展生态系统管理实践，以维持我们管理的森林生态系统的生态完整性。这需要对我们森林的自然动态、自然干扰机制以及自然干扰与人为干扰对其结构、功能和组成的影响的比较有很好的了解。该项目侧重于开发南北方混交木林分水平的生态系统管理实践。由于物种混合的多样性和自然干扰的多样性，这种森林类型具有复杂的动态。我们的总体目标是评估部分采伐在多大程度上产生了类似于该地区自然次灾难性干扰的林分属性，以及部分采伐在多大程度上是社会可接受的。我们的方法整合了三种程度的时间感知-过去，现在和未来-以及三种互补的方法方法（回顾性研究，造林试验和林分动态建模），以比较两种广泛类型的次生干扰，特别是云杉budworm爆发和风投事件（自然）与部分采伐（工业）。将对1960年至1980年间受到这两种干扰影响的林分进行清查，并比较其组成、直立和倒塌结构（活的和死的）、对干扰的生长反应和增补情况。在此基础上，建立了造林试验，比较不同的部分刈割处理（保留、直径限制、间隙刈割）和土壤表层扰动对林分组成、结构和幼苗招募的影响。最后，该项目的回顾和造林试验部分的数据将用于树级模型SORTIE，以比较模拟的未来林分对自然和工业干扰的反应。然后由一些当地利益集团（林业人员、环境保护主义者和非木材用途）评估不同的方案。该项目将提供一个框架，在此基础上为这一森林地区制定创新的造林和管理做法。

The development of ecosystem management practices is required to maintain the ecological integrity of our managed forest ecosystems. This requires a good knowledge of the natural dynamics of our forest, its natural disturbance regime, and a comparison of the effects of natural vs. human-induced disturbances on its structure, function and composition. This project focuses on developing ecosystem management practices at the stand-level for a southern boreal mixewood. This forest type has complex dynamics due a diverse species mix and a large variety of natural disturbances.  Our general objective is to evaluate the extent to which partial cutting generates stand attributes similar to natural sub-catastrophic disturbances in this region and to what extent partial harvesting scenarios are socially acceptable. Our approach integrates three degrees of temporal perception - past, present and future - and three complementary methodological approaches (retrospective studies, silvicultural trials and stand dynamics modelling) to compare two broad types of secondary disturbances, specifically spruce budworm outbreaks and windthrow events (natural) with partial harvesting (industrial). Stands that have been affected by either of these disturbances between 1960 and 1980 will be inventoried and compared for composition, standing and fallen structures (live and dead), growth response to disturbance and recruitment. Parallel to this study, silvicultural trials have been established to compare the effects of different partial cutting treatments (retention, diameter limit, gap cuts) and soil surface-layer disturbances on stand composition, structure and seedling recruitment. Finally, data from both the retrospective and silvicultural trial components of this project will be used in the tree-level model SORTIE for comparisons of simulated future stand responses to both natural and industrial disturbances. The different scenarios will then be evaluated by a number of local interest groups (foresters, environmentalists and non-timber uses). The project will provide a framework upon which innovative silvicultural and management practices will be developed for this forest region.