Del Toro Israel, Ribbons Relena R
Biology Department, Lawrence University, Appleton, WI, United States.
PeerJ. 2019 Apr 11;7:e6686. doi: 10.7717/peerj.6686. eCollection 2019.
Ant-mediated seed dispersal, also known as myrmecochory, is a widespread and important mutualism that structures both plant and ant communities. However, the extent to which ant functional types (e.g., granivorous generalists vs. myrmecochorous ants) across environmental gradients affect seed removal rates is not fully understood. We used a replicated, standardized seed removal experiment along elevation gradients in four mountain ranges in the southwestern United States to test predictions that: (1) seed removal rates would be greater at lower elevations, and (2) seed species identity influences seed removal rates (i.e., seeds from their native elevation range would be removed at higher rates than seeds outside of their native elevation range). Both predictions were supported. Seed removal rates were ∼25% higher at lower elevation sites than at higher elevation sites. The low elevation and high elevation were removed at higher rates in their respective native ranges. We attribute observed differences in dispersal rates to changes in ant community composition, functional diversity, and abundance. We also suggest that temperature variation along the elevation gradient may explain these differences in seed removal rates.
蚂蚁介导的种子传播，也称为蚁播，是一种广泛且重要的共生关系，它构建了植物群落和蚂蚁群落。然而，不同功能类型的蚂蚁（例如，食谷通才蚁与蚁播蚁）在环境梯度上对种子移除率的影响程度尚未完全了解。我们在美国西南部四个山脉沿海拔梯度进行了一项重复的、标准化的种子移除实验，以检验以下预测：（1）低海拔地区的种子移除率会更高，以及（2）种子物种身份会影响种子移除率（即来自其原生海拔范围的种子比来自其原生海拔范围之外的种子被移除的速率更高）。这两个预测均得到了支持。低海拔地区的种子移除率比高海拔地区高约25%。低海拔和高海拔种子在各自的原生范围内被移除的速率更高。我们将观察到的传播速率差异归因于蚂蚁群落组成、功能多样性和丰度的变化。我们还认为，沿海拔梯度的温度变化可能解释了这些种子移除率的差异。
