Research on mixed forests has mostly focused on tree growth and productivity, or resistance and resilience in changing climate conditions, but only rarely on the effects of tree species mixing on timber quality. In particular, it is still unclear whether the numerous positive effects of mixed forests on productivity and stability come at the expense of timber quality. In this study, we used photographs of sawn boards from 90 European beech (Fagus sylvatica L.) trees of mixed and pure forest stands to analyze internal timber quality through the quality indicator knot surface that was quantitatively assessed using the software Datinf® Measure. We observed a decrease in knot surface with increasing distance from the pith as well as smaller values in the lower log sections. Regarding the influence of neighborhood species identity, we found only minor effects meaning that timber qualities in mixed stands of beech and Norway spruce (Picea abies (L.) H. Karst.) tended to be slightly worse compared to pure beech stands.

对混交林的研究主要集中在树木的生长和生产力上，或者在不断变化的气候条件下的抵抗力和复原力，而很少涉及混种树木对木材质量的影响。尤其是，目前尚不清楚混合林对生产力和稳定性的众多积极影响是否以牺牲木材质量为代价。在这项研究中，我们使用了来自90棵欧洲山毛榉（Fagus sylvatica L.）混合和纯林林分的锯切板的照片，通过质量指标结表面分析内部木材质量，该质量指标结点使用Datinf®Measure软件进行了定量评估。我们观察到结面减少距木桩的距离增加，而下部对数部分的值较小。关于邻里物种身份的影响，我们发现只有很小的影响，这意味着山毛榉和挪威云杉（Picea abies（L.）H. Karst。）的混合林中的木材品质比纯山毛榉林要差一些。