Data from: The effects of habitat management on the species, phylogenetic and functional diversity of bees are modified by the environmental context

Anthropogenic landscape elements, such as roadsides, hedgerows, field edges, and power line clearings, can be managed to provide important habitats for wild bees. However, the effects of habitat improvement schemes in power line clearings on components of diversity are poorly studied. We conducted a large-scale experiment to test the effects of different management practices on the species, phylogenetic, and functional diversity of wild bees in power line clearings (n = 19 sites across southeastern Norway) and explored whether any treatment effects were modified by the environmental context. At each site, we conducted the following treatments: (1) Cut: all trees cut and left to decay in the clearing; (2) Cut + Remove: all trees cut and removed from the plot; and (3) Uncut: uncleared. The site-specific environmental context (i.e., elevation and floral diversity) influenced the species, phylogenetic, and functional diversity within bee species assemblages. The largest number of species was found in the Cut + Remove treatment in plots with a high forb species richness, indicating that the outcome of management practices depends on the environmental context. Clearing of treatment plots with many forb species also appeared to alter the phylogenetic composition of bee species assemblages, that is, more closely related species were found in the Cut and the Cut + Remove plots than in the Uncut plots. Synthesis and applications: Our experimental simulation of management practices in power line clearings influenced the species, phylogenetic, and functional diversity of bee species assemblages. Frequent clearing and removal of the woody debris at low elevations with a high forb species richness can increase the value of power line clearings for solitary bees. It is therefore important for managers to consider the environmental context when designing habitat improvement schemes for solitary bees.

人为景观要素（anthropogenic landscape elements），例如路边、树篱（hedgerows）、田埂以及输电线路清伐区（power line clearings），可通过合理管理为野生蜂类（wild bees）提供重要栖息生境。然而，目前针对输电线路清伐区的生境改善方案（habitat improvement schemes）对生物多样性各组分的影响，相关研究尚较为匮乏。

本研究开展了一项大规模野外实验，以探究不同管理措施对挪威东南部19个输电线路清伐区内野生蜂类的物种多样性（species diversity）、系统发育多样性（phylogenetic diversity）及功能多样性（functional diversity）的影响，并分析环境背景（environmental context）是否会对各处理组的效应产生调控作用。

每个试验样地（plot）均设置以下三种处理：（1）砍伐组：伐除所有树木并使其在清伐区内自然腐解；（2）砍伐移除组：伐除所有树木并将木质残体移出样地；（3）未砍伐组：保留原有植被，不开展清伐作业。

样地特有的环境背景（即海拔与开花植物多样性）会显著影响野生蜂类群落的物种、系统发育及功能多样性。在草本物种丰富度（forb species richness）较高的样地中，砍伐移除组的野生蜂物种数量最多，这表明管理措施的实施效果依赖于样地的环境背景。对草本物种丰富度较高的样地进行清伐处理，还会改变野生蜂类群落的系统发育组成：相较于未砍伐组，砍伐组与砍伐移除组样地内的蜂类物种亲缘关系更为紧密。

综合与应用：本研究通过模拟输电线路清伐区的不同管理措施，证实其会显著影响野生蜂类群落的物种、系统发育及功能多样性。在草本物种丰富度较高的低海拔区域，频繁清伐并移除木质残体，可提升输电线路清伐区对独居蜂（solitary bees）的栖息价值。因此，管理人员在设计独居蜂生境改善方案时，需充分考量样地的环境背景条件。