A meta-analysis of community response predictability to anthropogenic disturbances.

Disturbances often lead to changes in average values of community properties; however, disturbances can also affect the predictability of a community’s response. We performed a meta-analysis to determine how response predictability, defined as among-replicate variance in diversity and community abundance, is affected by species removals, species invasions, nutrient addition, temperature increase, and habitat loss/fragmentation, and we further determined whether response predictability differed according to habitat and trophic role. Species removals and nutrient addition decreased response predictability, while species invasions increased response predictability. In aquatic habitats, disturbances generally led to a decrease in response predictability, whereas terrestrial habitats showed no overall change in response predictability, suggesting that differences in food web and ecosystem structure affect how communities respond to disturbance. Producers were also more likely to show decreases in response predictability, particularly following species removals, highlighting widespread destabilizing effects of species loss at the producer level. Overall, our results show that whether disturbances cause changes in response predictability is highly contingent on disturbance type, habitat, and trophic role. The nature of changes in response predictability—for example, strong decreases following species invasions and increases following species removals—will likely play a major role in how communities recover from disturbance.

干扰通常会引发群落属性的平均值发生改变；但与此同时，干扰也会影响群落响应的可预测性。本研究通过元分析（meta-analysis）探究了物种移除、物种入侵、养分添加、温度升高以及生境丧失/破碎化等干扰因素对响应可预测性的影响——其中响应可预测性被定义为多样性与群落丰度的重复间方差；同时进一步分析了响应可预测性是否因生境类型与营养级角色的不同而存在差异。物种移除与养分添加会降低群落响应的可预测性，而物种入侵则会提升该可预测性。在水生生境中，各类干扰通常会降低群落响应的可预测性；而陆地生境的群落响应可预测性则未出现整体变化，这表明食物网与生态系统结构的差异会影响群落对干扰的响应模式。生产者（producer）群落的响应可预测性也更易出现下降，尤以物种移除事件后最为显著，这凸显了物种丧失对生产者层级普遍存在的失稳效应。总体而言，本研究结果表明，干扰是否会引发群落响应可预测性的改变，高度取决于干扰类型、生境类型以及营养级角色。群落响应可预测性的变化特征——例如物种入侵后可预测性大幅下降，而物种移除后可预测性上升——或将在群落从干扰中恢复的过程中发挥关键作用。