Key message

Drivers of the abundance and richness of tree-related microhabitats are similar in mountain forests of Europe and North America and their occurrence may be explained by tree functional groups.

Abstract

A common approach to support forest-dwelling species in managed forests is to preserve valuable habitat trees. To assess the quality of habitat trees, a hierarchical typology of tree-related microhabitats (TreMs) is applied in the European context for inventory standardization. The first aim of this study was to evaluate whether it is possible to use this hierarchical typology as a standard protocol regardless of location, which is important for potentially standardizing future studies of TreMs, by testing whether the typology could be applied to the western North American mountain forests of Idaho. The second aim of the study was to analyse drivers that influence TreMs in forests of the region. Thirdly, we assessed whether the occurrence of TreMs could be explained by functional groups of trees across the western mountain forests of Idaho and Central European mountain forests, using TreM inventory data previously collected in the Black Forest, Germany. Abundance and richness of TreMs per tree were analyzed as a function of tree species, live status (dead vs. live trees), diameter at breast height (DBH), and site factors (latitude and altitude). Our results show that the TreM typology could be applied with slight modifications in the forests of Idaho. The abundance and richness of TreMs per tree increased with DBH. Snags offered more TreMs per tree than live trees. We were able to group tree species from the two continents in functional groups that were related to the occurrence of certain TreMs. Tree functional groups offer an opportunity to predict the role of certain tree species for habitat provision through TreMs. Combinations of trees from different functional groups could be used to optimize provisioning of TreMs within forest stands.

中文翻译：

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与树木有关的微生境在欧洲和北美的山区森林中相似，它们的发生可能由树木功能组解释

关键信息

与树木有关的微生境的丰富性和丰富性的驱动因素在欧洲和北美的山区森林中是相似的，它们的发生可能由树木功能组来解释。

抽象

在管理的森林中支持森林居住物种的一种常见方法是保存宝贵的栖息地树木。为了评估栖息地树木的质量，在欧洲范围内应用了与树木相关的微栖息地（TreMs）的分层类型，以进行清单标准化。这项研究的第一个目的是评估是否可以使用这种分层类型学作为标准协议，而不论其位置如何，这通过测试该类型学是否可以应用于北美西部，对于潜在地对TreM的未来研究进行标准化很重要。爱达荷州的高山森林。该研究的第二个目的是分析影响该地区森林TreM的驱动因素。第三，我们使用先前在德国黑森林中收集的TreM清单数据，评估了TreM的发生是否可以由爱达荷州西部山区森林和中欧山区森林中的树木功能组解释。分析了每棵树的TreM的丰富度和丰富度，这些变化是树种，生活状况（枯死树与活树），胸高（DBH）的直径和地点因素（纬度和高度）的函数。我们的结果表明TreM类型学可以在爱达荷州的森林中稍加修改即可应用。每棵树的TreM的丰度和丰富度随着DBH的增加而增加。障碍提供的每棵树的TreM数量比活树更多。我们能够将来自两大洲的树种按与某些TreM发生有关的功能分组。树木功能组提供了一个机会，可以预测某些树木物种通过TreM提供栖息地的作用。来自不同功能组的树木的组合可用于优化林分中TreM的配置。