In this study the influence of forest management on the characteristics of snags and tree cavities in the Hyrcanian forests of Iran was investigated. In particular, the effect of two sylvicultural treatments (shelter wood and single-tree selection) was assessed in comparison to protected stands. The abundance, diameter, height, and degree of decay of snag species, and the characteristics of birds excavated and natural cavities (number and height from the ground level) were measured by systematic plots in each stand. The results showed that the abundance, species diversity, and size of snags in both of the sylvicultural treatments were significantly lower than the protected stands. The number of birds excavated and natural cavities on thicker snags with moderate decay was significantly higher than other decay classes. Abundance, species diversity, size of snags, and number of tree cavities in the single-tree selection stands were significantly higher than sheltered-wood stands.

中文翻译：

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森林管理和林木栽培处理对山毛榉混交林中大量障碍物和树洞的影响

在这项研究中，调查了森林管理对伊朗希尔卡尼亚森林中障碍物和树洞特征的影响。特别是，与受保护林分相比，评估了两种森林栽培处理（遮蔽木材和单树选择）的效果。通过每个林分的系统地块测量了断枝物种的丰度、直径、高度和腐烂程度，以及挖掘出的鸟类和自然空洞的特征（数量和距离地面的高度）。结果表明，两个林木栽培处理的丰度、物种多样性和断枝大小均显着低于保护林。在中等腐烂的较厚障碍物上挖掘的鸟类数量和自然空洞的数量明显高于其他腐烂类别。丰富，物种多样性，