Data from: Interactive effects of disturbance and dispersal on community assembly

The traditional debate on alternative community states has been over whether or not they exist. Studies of community assembly have examined the role of assembly history in driving community divergence, but the context in which assembly history becomes important is a continued topic of interest. In this study, we created communities of bacterivorous ciliated protists in laboratory microcosms and manipulated assembly history, disturbance frequency, and the presence of dispersal among local communities to investigate the mechanisms behind community divergence. Specifically, we sought to understand how the role of assembly history changed in response to disturbance, dispersal, and the combination of the two. Assembly history influenced the identity of the dominant species through priority effects, and dispersal and disturbance showed interactive effects on both alpha and beta diversity. Dispersal increased alpha diversity, but only in the absence of disturbance, and it reduced beta diversity, but not in the presence of low or mixed disturbance. These results demonstrate that the role of assembly history and the strength of priority effects depend on community context, suggesting that understanding the interactions between various factors shaping community assembly is important for understanding how ecological communities are structured.传统上关于群落交替状态的争论焦点在于其是否真实存在。现有群落装配（community assembly）研究已探讨过装配历史（assembly history）对群落分异的驱动作用，但装配历史发挥重要功能的具体情境仍是学界持续关注的议题。本研究通过实验室微宇宙（laboratory microcosms）体系构建食细菌纤毛原生生物（bacterivorous ciliated protists）群落，并对装配历史、干扰频率以及本地群落间的扩散（dispersal）进行实验操控，以探究群落分异背后的作用机制。具体而言，本研究旨在阐明装配历史的作用如何随干扰、扩散以及二者的联合作用发生变化。研究发现，装配历史通过优先效应（priority effects）影响优势物种的群落组成；扩散与干扰对α多样性（alpha diversity）和β多样性（beta diversity）均存在交互调控效应：扩散可提升α多样性，但仅在无干扰的情境下生效；同时扩散会降低β多样性，但在低干扰或混合干扰条件下这一效应并不显著。本研究结果表明，装配历史的作用强度与优先效应的强弱均依赖于群落背景，这意味着厘清塑造群落装配的各类因子间的交互关系，对于理解生态群落的构建机制至关重要。