Data from: Species turnover through time: colonization and extinction dynamics across metacommunities

Island biogeography and metacommunity theory often use equilibrium assumptions to predict local diversity, yet non-equilibrium dynamics are common in nature. In non-equilibrium communities, local diversity fluctuates through time as the relative importance of colonization and extirpation change. Here, we test the prevalence and causes of non-equilibrium dynamics in metacommunities of mites associated with rubber trees distributed over large spatial (>1000 km) and temporal (> 30-60 generations) scales in Brazil. We measured colonization and extirpation rates to test species turnover and non-equilibrium dynamics over a growing season. Mite metacommunities exhibited non-equilibrium dynamics for most months of the year, and these dynamics tracked climatic conditions. Monthly shifts in temperature of more than one degree Celsius resulted in non-equilibrium dynamics, as did mean temperatures outside of two critical ranges. Non-equilibrium dynamics were caused by a change in colonization with temperature change, and changes in both colonization and extirpation with absolute temperature. Species turnover showed different trends; high relative humidity increased both colonization and extirpation rates, increasing turnover but not non-equilibrium dynamics. Our study illustrates that testing non-equilibrium dynamics can provide new insights into the drivers of colonization, extinction and diversity fluctuations in metacommunities.岛屿生物地理学（Island biogeography）与集合群落理论（metacommunity theory）常借助平衡态假设预测局域多样性（local diversity），但非平衡动态（non-equilibrium dynamics）在自然界中普遍存在。在非平衡群落中，随着定殖（colonization）与局部绝灭（extirpation）的相对重要性发生变化，局域多样性会随时间产生波动。本研究针对巴西境内分布于大空间尺度（>1000千米）与大时间尺度（>30-60个世代）的橡胶树附生螨类集合群落（metacommunity），检验了非平衡动态的普遍性及其成因。我们测定了定殖速率与局部绝灭速率，以检验一个生长季内的物种周转（species turnover）与非平衡动态。螨类集合群落一年中的多数月份均表现出非平衡动态，且此类动态与气候条件密切关联。月温度波动超过1摄氏度，以及平均温度超出两个临界区间时，均会引发非平衡动态。非平衡动态由温度变化引发的定殖速率改变，以及绝对温度变化带来的定殖与局部绝灭速率双重改变所驱动。物种周转则呈现出不同的趋势：高相对湿度会同时提升定殖与局部绝灭速率，从而加快物种周转，但不会引发非平衡动态。本研究表明，对非平衡动态的检验能够为集合群落中定殖、绝灭与多样性波动的驱动因子提供全新的认知视角。