While land use intensification is a major driver of biodiversity change in streams, the nature of such changes, and at which scales they occur, have not been synthesized. To synthesize how land use change has altered multiple components of stream biodiversity across scales, we compiled data from 37 studies where comparative data were available for species' total and relative abundances from multiple locations including reference (less impacted) streams to those surrounded by different land use types (urban, forestry, and agriculture). We found that each type of land use reduced multiple components of within-stream biodiversity across scales, but that urbanization consistently had the strongest effects. However, we found that β-diversity among streams in modified landscapes did not differ from β-diversity observed among reference streams, suggesting little evidence for biotic homogenization. Nevertheless, assemblage composition did experience considerable species turnover between reference and modified streams. Our results emphasize that to understand how anthropogenic factors such as land use alter biodiversity, multiple components of biodiversity within and among sites must be simultaneously considered at multiple scales.

中文翻译：

---

土地利用对跨指标和尺度的河流生物多样性影响的综合

虽然土地利用集约化是河流生物多样性变化的主要驱动因素，但尚未综合分析此类变化的性质及其发生的规模。为了综合土地利用变化如何跨尺度改变河流生物多样性的多个组成部分，我们汇编了 37 项研究的数据，这些研究提供了来自多个地点的物种总丰度和相对丰度的比较数据，包括参考（受影响较小的）河流到被不同土地包围的河流使用类型（城市、林业和农业）。我们发现，每种土地利用类型都会在不同尺度上减少河流内生物多样性的多个组成部分，但城市化始终具有最强的影响。然而，我们发现修改景观中溪流之间的 β 多样性与参考溪流中观察到的 β 多样性没有区别，表明生物同质化的证据很少。尽管如此，组合组成确实在参考流和修改流之间经历了相当大的物种周转。我们的研究结果强调，要了解土地利用等人为因素如何改变生物多样性，必须在多个尺度上同时考虑地点内和地点之间生物多样性的多个组成部分。