Objectives

Harmful effects of habitat loss and fragmentation can be detected across multiple spatial scales, yet most studies that aim to characterize these effects take place at a single spatial scale. Here we investigated responses in ant diversity to forest fragmentation across three spatial scales.

Methods

We sampled ant diversity in a fragmented landscape in southeastern Brazil. We set transects with 15 pitfall traps (local scale response) within 16 forest fragments (fragment scale response) distributed in eight paired fragments separated by roads (mesoscale response). We measured habitat features at local, fragment and mesoscales and across the landscape. For each spatial scale, we then assessed the effects of ecological drivers measured at the same and subsequent higher spatial scales.

Results

Local diversity was higher with closer proximity to the matrix, and in fragments with high vegetation density. Both fragment species richness and β-diversity were higher in less circular fragments. However, at the mesoscale (pairs of fragments), total species richness decreased with increasing pasture matrix in the landscape (landscape driver).

Conclusions

Edge and matrix effects lead to increased ant species richness at small spatial scales (due to an increase in generalist ants). However, when analyzed at a higher spatial scale, the responses to these effects were in fact reversed, leading to a decrease in ant diversity. Thus, we suggest that conservation efforts should take a multi-scale perspective (from local to landscape) and aim to protect both local and fragment characteristics that can buffer edge effects, as well as improve matrix quality in the landscape.

中文翻译：

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边缘和牧场矩阵对不同空间尺度上零散景观中蚂蚁多样性的影响

目标

可以在多个空间尺度上检测到栖息地丧失和破碎化的有害影响，但是大多数旨在表征这些影响的研究都是在单个空间尺度上进行的。在这里，我们研究了蚂蚁多样性对跨三个空间尺度的森林破碎化的响应。

方法

我们在巴西东南部一个零散的景观中采样了蚂蚁多样性。我们在16个森林片段（片段尺度响应）中设置了15个陷阱陷阱（局部尺度响应），这些剖面分布在由道路分隔的八个成对片段（中尺度响应）中。我们测量了局部，片段和中尺度以及整个景观的栖息地特征。然后，对于每个空间尺度，我们评估了在相同及随后更高的空间尺度下测得的生态驱动力的影响。

结果

靠近基质的地方以及在具有高植被密度的碎片中，局部多样性较高。圆环状的碎片较少，碎片种类的丰富度和β多样性都较高。但是，在中尺度（成对的碎片）上，总物种丰富度随着景观中牧场矩阵的增加而降低（景观驱动力）。

结论

边缘效应和基质效应导致小空间尺度上的蚂蚁物种丰富度增加（由于通才蚁的数量增加）。但是，在更高的空间尺度上进行分析时，实际上对这些效应的反应是相反的，从而导致蚂蚁多样性降低。因此，我们建议保护工作应采取多尺度的观点（从局部到景观），并旨在保护局部和碎片特征，这些特征可以缓冲边缘效应，并改善景观中的基质质量。