Animals alter precipitation legacies: trophic and ecosystem engineering effects on plant community temporal dynamics

1. Multi-year precipitation ‘legacies’ can have stronger effects on plant community composition than rainfall in the current growing season, but variation in the magnitude of these effects is not fully understood. Direct interactions between plants and animals, such as herbivory, and indirect interactions, such as ecosystem engineering (via changes in the physical environment), may influence precipitation legacies by altering mechanisms of lagged effects. However, the role of direct and indirect plant-animal interactions in determining the strength of precipitation legacies remains largely unexplored. 2. Here, we investigated effects of current growing season rainfall and precipitation legacies on grassland composition, and the influence of herbivory and ecosystem engineering interactions on these temporal dynamics. From 2009 to 2014, a period spanning high and low rainfall, we recorded plant cover in kangaroo rat exclosures and paired control plots that included both burrow and inter-b...

1. 多年尺度的降水遗留效应（precipitation legacies）对植物群落组成的影响可能强于当前生长季降雨的作用，但其效应强度的变异机制尚未完全明晰。植物与动物间的直接相互作用（如植食作用）及间接相互作用（如生态系统工程（ecosystem engineering）——通过改变物理环境实现），或许会通过改变滞后效应的作用机制来影响降水遗留效应。然而，动植物直接与间接相互作用在决定降水遗留效应强度中的角色，目前仍大多未被探索。
2. 本研究探讨了当前生长季降雨与降水遗留效应对草地群落组成的影响，以及植食作用与生态系统工程相互作用对这些时间动态的调控。在2009至2014年这一涵盖干湿降水梯度的时期内，我们在更格卢鼠排除样地及包含洞穴与洞穴间区域的配对对照样地中，记录了植物盖度……