Data from: Synchrony in small mammal community dynamics across a forested landscape

Long-term studies at local scales indicate that fluctuations in abundance among trophically similar species are often temporally synchronized. Complementary studies on synchrony across larger spatial extents are less common, as are studies that investigate the subsequent impacts on community dynamics across the landscape. We investigate the impact of species population fluctuations on concordance in community dynamics for the small mammal fauna of the White Mountain National Forest, USA. Hierarchical open population models, which account for imperfect detection, were used to model abundance of the most common species at 108 sites over a three year period. Most species displayed individualistic responses of abundance to forest type and physiographic characteristics. However, among species, we found marked synchrony in population fluctuations across years, regardless of landscape affinities or trophic level. Across the region, this population synchrony led to high within-year concordance of community composition and aggregate properties (e.g., richness and diversity) independent of forest type and low among-year similarity in communities, even for years with similar species richness. Results suggest that extrinsic factors primarily drive abundance fluctuations and subsequently community dynamics, although local community assembly may be modified by species dispersal abilities and biotic interactions. Concordant community dynamics across space and over time may impact the stability of regional food webs and ecosystem functions.局域尺度的长期研究显示，营养级相似的物种种群丰度波动通常具有时间同步性。针对更大空间尺度下种群同步性的补充研究相对稀缺，而探究此类同步性对区域全域群落动态产生后续影响的研究亦较为少见。本研究以美国怀特山国家森林公园的小型哺乳动物类群为研究对象，旨在揭示物种种群波动对群落动态一致性的影响。研究采用考虑检测不完全性的分层开放种群模型（Hierarchical open population models），对三年间108个调查样地内优势物种种群的丰度进行建模分析。多数物种种群丰度对森林类型及地貌特征呈现出物种特异性的响应模式。然而，研究发现，无论物种的景观偏好或营养级（trophic level）如何，各物种种群波动在多年间均表现出显著的同步性。在该区域范围内，这种种群同步性使得群落组成及群落聚合属性（如物种丰富度、多样性）在年内呈现高度一致性，且该特征不受森林类型影响；同时，即便部分年份的物种丰富度相近，群落的年际相似性仍处于较低水平。研究结果表明，尽管局域群落组装过程可能会受到物种种群扩散能力与生物相互作用的调控，但物种种群丰度波动及后续群落动态主要由外源因素驱动。空间与时间维度上的群落动态同步性，可能会对区域食物网及生态系统功能的稳定性产生潜在影响。