Data_Sheet_1_Integrating Disturbance, Seasonality, Multi-Year Temporal Dynamics, and Dormancy Into the Dynamics and Conservation of Metacommunities.docx

The metacommunity framework has rapidly become a dominant concept used by ecologists to understand community assembly. By emphasizing extinction-colonization dynamics, dispersal, and species’ niche requirements in determining community structure, metacommunity theory unifies local and regional processes as integral to species distributions across landscapes. Metacommunity structure has traditionally been treated as static. However, habitat characteristics and community composition can shift through time because of factors like seasonal dynamics, ecosystem disturbance, multi-year climate variation (e.g., El Niño Southern Oscillation), and production and emergence of dormant propagules. In most systems, the relevance of such temporal variation for the structure and persistence of metacommunities is an open question that is of potential importance for conservation and management. We evaluate and synthesize the theory and concepts relevant to four major forms of temporal dynamics that are pertinent to metacommunities: disturbance, seasonality, multi-year climate variation, and dormancy. For each type of dynamic we review the theoretical underpinnings and empirical evidence to evaluate how the dynamic drives temporal variation in metacommunity structure. We also consider how major forms of anthropogenic change further influence these patterns. Our survey highlights that seasonal climatic differences can modify the distribution and availability of resources and connectivity, with consequences for species’ use of the landscape and species interactions. Disturbance and multi-year climate cycles can increase the importance of dispersal, but implications for environmental filtering and species interactions remain unresolved. Dormant life stages serve to anchor habitat patches and species pools in space and highlight the importance of dispersal-dormancy tradeoffs and environmental variation for metacommunity structure. Temporal variability in biotic and abiotic conditions associated with these drivers can modify the relative strengths of dispersal, environmental filtering, and species interactions, three biological processes that drive metacommunity structure. Inclusion of spatiotemporal drivers creates patterns of species diversity that differ from traditional metacommunity ideas. We use these insights to highlight research needs, suggest a reconceptualization of metacommunities as undergoing continuous change, and discuss the implications of temporal dynamism for the conservation and management of metacommunities.

元群落框架迅速成为生态学家用以理解群落组装的占主导地位的概念。通过强调灭绝-殖民动态、扩散以及物种生态位需求在决定群落结构中的作用，元群落理论将局部和区域过程视为物种在景观中分布的不可或缺的组成部分。元群落结构传统上被视为静态的。然而，由于季节性动态、生态系统扰动、多年气候变化（例如，厄尔尼诺南方涛动）、休眠种子的生产和出现等因素，栖息地特征和群落组成可能随时间推移而变化。在大多数系统中，这种时间变化对于元群落结构和持续性的相关性是一个悬而未决的问题，对保护和管理具有潜在的的重要性。我们评估和综合了与元群落相关的时间动态四种主要形式的理论与概念：干扰、季节性、多年气候变化和休眠。对于每种动态，我们回顾了其理论依据和经验证据，以评估这种动态如何驱动元群落结构的时间变化。我们还考虑了主要的人为变化如何进一步影响这些模式。我们的研究突出了季节性气候差异可以改变资源和连通性的分布和可用性，对物种利用景观和物种相互作用产生后果。干扰和多年气候变化可以增加扩散的重要性，但环境筛选和物种相互作用的影响尚待解决。休眠生命阶段有助于在空间上锚定栖息地斑块和物种库，突出了扩散-休眠权衡和环境影响对元群落结构的重要性。与这些驱动因素相关的生物和非生物条件的时间变化可以改变扩散、环境筛选和物种相互作用相对强度的相对优势，这三个生物学过程是驱动元群落结构的力量。包含时空驱动因素创造了与传统元群落理念不同的物种多样性模式。我们利用这些见解来强调研究需求，建议将元群落重新概念化为持续变化的过程，并讨论时间动态对元群落保护和管理的启示。