1. The composition of spider communities in forests is affected by habitat characteristics, such as canopy openness, vegetation cover or tree species diversity; therefore, we assume that the effect of canopy will differ among tree species.
2. As research in European beech forests has not been conducted, we studied the effect of understory environmental characteristics associated with a gradient of overstory canopy openness in beech forest on ground‐dwelling spider richness, abundance and guild composition in the Western Carpathians, Slovakia. Canopy openness, the cover of understory vegetation and litter, litter thickness and variability and soil reaction were recorded. In total, 17 332 individuals of 174 spider species were trapped during 518 days. We used Generalised Linear Models to explain the effect of environmental characteristics on the assemblages of ground‐dwelling spiders; the unique and shared contributions of the predictors were calculated using variation partitioning.
3. The association of canopy openness with spider species richness was hump‐shaped and displayed positive linear relationship with abundance. Abundance was also affected by soil pH.
4. The composition of spider communities was significantly affected by canopy openness and understory characteristics; a major part of this variation was shared between all variables. The guild composition of the assemblages interacted with canopy openness, as sheet‐web weavers were dominant under the most closed canopy, that below 20% of canopy openness, while ground hunters dominated in the rest of the canopy gradient.
5. The gradient of beech forest canopy openness affected spider species richness, abundance and guild composition and supported distinct assemblages.

中文翻译：

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欧洲山毛榉（Fagus sylvatica）森林的林冠开放度对地面蜘蛛群落的影响

1. 森林中蜘蛛群落的组成受到生境特征的影响，例如冠层的开放度，植被覆盖度或树木物种的多样性。因此，我们假设树冠的效果在树种之间会有所不同。
2. 由于尚未进行欧洲山毛榉林的研究，因此我们研究了山毛榉林下层环境特征与过高的树冠开放度梯度相关联对斯洛伐克西部喀尔巴阡山脉的地面居住蜘蛛的丰富度，丰度和行会组成的影响。记录冠层开放度，林下植被和凋落物的覆盖，凋落物的厚度和变异性以及土壤反应。在518天内，总共捕获了174种蜘蛛的17332个人。我们使用广义线性模型来解释环境特征对地面蜘蛛集结的影响。使用变异划分来计算预测变量的唯一和共享贡献。
3. 冠层开放度与蜘蛛物种丰富度之间的联系呈驼峰状，与丰度呈线性关系。土壤的pH值也影响丰度。
4. 蜘蛛群落的组成受冠层开放度和林下特征的影响很大。所有变量之间都共享这种差异的很大一部分。组合的行会组成与树冠的开放性相互作用，因为在最封闭的树冠下，薄板织布机占主导地位，低于树冠开放度的20％，而在其余的树冠梯度中，地面狩猎者占主导地位。
5. 山毛榉林冠层开放度的梯度影响蜘蛛物种的丰富性，丰度和行会组成，并支持不同的组合。