Institute of Evolution and Ecology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China.
Department of Biology, Wilkes University, Wilkes-Barre, 18766, USA.
Sci China Life Sci. 2024 Jul;67(7):1514-1524. doi: 10.1007/s11427-023-2517-1. Epub 2024 Mar 25.
The significance of ecological non-monotonicity (a function whose first derivative changes signs) in shaping the structure and functions of the ecosystem has recently been recognized, but such studies involving high-order interactions are rare. Here, we have proposed a three-trophic conceptual diagram on interactions among trees, rodents, and insects in mast and non-mast years and tested the hypothesis that oak (Quercus wutaishanica) masting could result in increased mutualism and less predation in an oak-weevil-rodent system in a warm temperate forest of China. Our 14-year dataset revealed that mast years coincided with a relatively low rodent abundance but a high weevil abundance. Masting not only benefited seedling recruitment of oaks through increased dispersal by rodents but also a decrease in predation by rodents and weevils, as well as an increase in the overwintering survival of rodents. Masting appeared to have increased weevil survival by reducing predation of infested acorns by rodents. These results suggest that masting benefits all participants in the plant-insect-rodent system by increasing mutualism and reducing predation behavior (i.e., a non-monotonic function). Our study highlights the significance of masting in maintaining the diversity and function of the forest ecosystem by facilitating the transformation from predation to mutualism among trophic species.
生态非单调（一阶导数改变符号的函数）在塑造生态系统的结构和功能方面的意义最近得到了认可，但涉及高阶相互作用的此类研究很少。在这里，我们提出了一个关于树木、啮齿动物和昆虫在结实年和非结实年之间相互作用的三营养级概念图，并检验了以下假设：在中国暖温带森林中，栎属（Quercus wutaishanica）结实可能导致栎象-鼠-虫系统中的共生增加和捕食减少。我们的 14 年数据集显示，结实年与相对较低的啮齿动物丰度和较高的象鼻虫丰度相吻合。结实不仅通过啮齿动物的传播增加了栎树幼苗的繁殖，而且减少了啮齿动物和象鼻虫的捕食，以及啮齿动物的越冬存活率。结实似乎通过减少啮齿动物对受感染橡子的捕食，增加了象鼻虫的存活率。这些结果表明，结实通过促进捕食者向共生关系的转变，从而增加了互惠关系并减少了捕食行为（即非单调函数），使植物-昆虫-啮齿动物系统中的所有参与者受益。我们的研究强调了结实通过促进营养物种之间从捕食到共生的转变，对维持森林生态系统的多样性和功能的重要性。
