Data from: Edge effects and beta diversity in ground and canopy beetle communities of fragmented subtropical forest

Clearing of dry forests globally creates edges between remnant forest and open anthropogenic habitats. We used flight intercept traps to evaluate how forest beetle communities are influenced by distance from such edges, together with vertical height, spatial location, and local vegetation structure, in an urbanising region (Brisbane, Australia). Species composition (but not total abundance or richness) differed greatly between ground and canopy. Species composition also varied strongly among sites at both ground and canopy levels, but almost all other significant effects occurred only at ground level, where: species richness declined from edge to interior; composition differed between positions near edges (<10 m) and interiors (> 50 m); high local canopy cover was associated with greater total abundance and richness and differing composition; and greater distances to the city centre were associated with increased total abundances and altered composition. Analyses of individual indicator species associated with this variation enabled further biological interpretations. A global literature synthesis showed that most spatially well-replicated studies of edge effects on ground-level beetles within forest fragments have likewise found that positions within tens of metres from edges with open anthropogenic habitats had increased species richness and different compositions from forest interior sites, with fewer effects on abundance. Accordingly, negative edge effects will not prevent relatively small compact fragments (if >10-20 ha) from supporting forest-like beetle communities, although indirect consequences of habitat degradation remain a threat. Retention of multiple spatially scattered forest areas will also be important in conserving forest-dependent beetles, given high levels of between-site diversity.

全球干旱森林的采伐清理会在残存森林与受人类活动干扰的开阔生境之间形成林缘带。本研究采用飞行拦截诱捕器（flight intercept traps），在澳大利亚布里斯班这一城市化区域中，探究森林甲虫群落受林缘距离、垂直高度、空间位置以及本地植被结构的影响。
物种组成（而非总个体丰度或物种丰富度）在地面层与冠层之间存在显著分化。物种组成在地面层和冠层的各采样位点间同样存在显著差异，但其余绝大多数显著效应仅出现在地面层：物种丰富度从林缘向林内逐步降低；林缘附近（<10米）与林内（>50米）的物种组成存在显著差异；本地冠层覆盖度较高的区域，总个体丰度与物种丰富度更高，且物种组成存在差异；距离城市中心越远的区域，总个体丰度越高，物种组成也发生改变。针对与该变异相关的单一指示物种开展分析，可进一步获得生物学层面的解读。
一项全球文献综合综述显示，绝大多数针对森林片段内地面甲虫林缘效应的高空间重复度研究均得到了相似结论：与开阔人工生境林缘数十米范围内的区域相比，林内生境的物种丰富度更高、物种组成存在差异，而对个体丰度的影响则相对有限。据此，负向林缘效应不会阻碍相对小型紧凑的森林片段（若面积大于10-20公顷）维持类同原生森林的甲虫群落，尽管生境退化带来的间接后果仍是一项潜在威胁。鉴于样点间的物种多样性水平较高，保留多个空间分散的森林区域对保护依赖森林的甲虫物种同样至关重要。