Multiple factors operating across different spatial and temporal scales affect β‐diversity, the variation in community composition among sites. Disentangling the relative influence of co‐occurring ecological drivers over broad biogeographic gradients and time is critical to developing mechanistic understanding of community responses to natural environmental heterogeneity as well as predicting the effects of anthropogenic change. We partitioned taxonomic β‐diversity in phytoplankton communities across 75 north‐temperate lakes and reservoirs in Alberta, Canada, using data‐driven, spatially constrained null models to differentiate between spatially structured, spatially independent, and spuriously correlated associations with a suite of biologically relevant environmental variables. Phytoplankton β‐diversity was largely independent of space, indicating spatial processes (e.g., dispersal limitation) likely play a minor role in structuring communities at the regional scale. Our analysis also identified seasonal differences in the importance of environmental factors, suggesting a general shift toward greater relevance of local, in‐lake (e.g., nutrients and Secchi depth) over regional, atmospheric and catchment‐level (e.g., monthly solar radiation and grassland coverage) drivers as the open‐water growing season progressed. Several local and regional variables explained taxonomic variation jointly, reflecting climatic and land‐use linkages (e.g., air temperature and water column stability or pastureland and nutrient enrichment) that underscore the importance of understanding how phytoplankton communities integrate, and may serve as sentinels of, broader anthropogenic changes. We also discovered similar community composition in natural and constructed water bodies, demonstrating rapid filtering of regional species to match local environmental conditions in reservoirs comparable to those in natural habitats. Finally, certain factors related to human footprint (e.g., cropland development) explained the composition of bloom‐forming and/or toxic cyanobacteria more than the overall phytoplankton community, suggesting their heightened importance to integrated watershed management.

中文翻译：

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温带湖泊中浮游植物群落的多尺度驱动因素。

跨不同时空尺度运作的多个因素会影响β多样性，即站点之间社区组成的变化。消除共同出现的生态驱动因素对广泛的生物地理梯度和时间的相对影响，对于发展对社区对自然环境异质性反应的机械理解以及预测人为变化的影响至关重要。我们使用数据驱动的，受空间限制的无效模型，在加拿大艾伯塔省75个北温带湖泊和水库的浮游植物群落中划分生物分类学β多样性，以区分空间结构，空间独立和虚假关联的关联以及一组生物学相关的关联环境变量。浮游植物的β多样性在很大程度上与空间无关，表明空间过程（例如，扩散限制）可能在区域规模的社区构建中起次要作用。我们的分析还确定了环境因素重要性方面的季节性差异，表明总体上已转向区域，大气层和集水区（例如每月太阳辐射和草地）与区域内，湖中（如营养物质和塞奇深度）的相关性更高随着开放水域生长季节的进展 几个局部和区域变量共同解释了生物分类的变化，反映了气候和土地利用的联系（例如，气温和水柱稳定性或牧场和养分富集），强调了了解浮游植物群落如何整合的重要性，并可能成为浮游生物的定点。更广泛的人为变化。我们还发现了自然水体和人工水体中类似的群落组成，这表明对地区物种进行了快速过滤，以匹配水库中与自然栖息地相当的当地环境条件。最后，与人类足迹有关的某些因素（例如农田发展）比整个浮游植物群落更能说明水华形成和/或有毒蓝细菌的组成，表明它们对综合流域管理的重要性日益增加。