Tree-related microhabitats (TreMs) provide ecological niches in features for a variety of species in forests and are suitable indicators of biodiversity for certain taxa. The study objective was to compare the abundance and occurrence of TreMs in managed versus unmanaged Oriental beech (Fagus orientalis Lipsky) forests of northern Iran to quantify the effect of forest management on biodiversity indicators. We inventoried 3,954 trees to identify the number of trees with TreMs and quantify the occurrence of different types of TreMs. Managed forests averaged 25 trees with TreMs per hectare, and unmanaged forests averaged 41 trees with TreMs per hectare. In both forests, larger-diameter trees (≥50 centimeters diameter at breast height [dbh]) had more TreMs than smaller-diameter trees. TreMs were found on trees larger than a minimum size (32 centimeters dbh) and were more common on trees in poor health, as indicated by vitality class. According to our findings, managed forests have a lower diversity of TreMs than unmanaged forests. However, if management plans in deciduous forests include the retention of large-diameter trees during harvesting events, it is possible to balance providing TreMs within the forest while maintaining growth of economically valuable timber.

中文翻译：

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与树木相关的微生境：伊朗北部以管理和未管理的东方山毛榉为主的森林的比较

与树木有关的微生境（TreMs）为森林中的各种物种提供了生态位，并且是某些分类单元生物多样性的合适指标。这项研究的目标是比较TreMs的丰度和发生在托管与非托管东方山毛榉（山毛榉侧柏伊朗北部的森林）以量化森林管理对生物多样性指标的影响。我们盘点了3,954棵树，以识别带有TreM的树的数量，并量化不同类型TreM的发生。人工林平均每公顷有25棵树木，每公顷TreM。在这两个森林中，直径较大的树木（胸高[dbh]处直径≥50厘米）比直径较小的树木具有更多的TreM。TreMs在大于最小大小（32厘米dbh）的树木上发现，并且在生命力较差的树木上更常见，如生命力等级所示。根据我们的发现，与非管理型森林相比，管理型森林的TreM多样性较低。但是，如果落叶林的管理计划包括在采伐期间保留大直径树木，