The relationship between biodiversity and ecosystem functioning, and the mechanisms underpinning the food web stability, have been intensively investigated in ecological research. The ubiquities of generalists in natural food webs and its important role in dictating these ecosystem properties have been generally recognized. However, how competition between multiple top predators shape these ecosystem properties and determine the success of invasive predators remain largely unexplored. Here, we use a well-developed food web model to investigate the effects of prey preference of top predators on ecosystem functioning and food web stability in both local and invasive conditions. We design several modeling scenarios to mimic combinations of different types of top predators (specialist/generalist) and their origins (local/invasive). Our model theoretically shows that lower exploitation competition for prey between top predators (with distinct prey preferences featured by higher attack rates) would be beneficial for the ecosystem functioning and food web stability. We also demonstrate that the success of top predator invasion depends on the prey preference of both local and invasive top predators. Sensitivity analysis on the model further supports our findings. Our results highlight the importance of prey preference of multiple top predators in manipulating the properties of multi-trophic ecosystems. Our findings may have important implications because the current ongoing global changes profoundly change the phenology of many biological systems and create trophic mismatch, which may manipulate prey preference of top predators and in turn deteriorate ecosystem functioning and food web stability.

在生态研究中，已经对生物多样性与生态系统功能之间的关系以及支撑食物网稳定性的机制进行了深入研究。天然食品网中通才的普遍性及其在决定这些生态系统特性方面的重要作用已得到普遍认可。然而，在很大程度上尚待探索多个顶级捕食者之间的竞争如何塑造这些生态系统特性并确定侵入性捕食者的成功。在这里，我们使用发达的食物网模型来研究顶级捕食者的猎物偏好在局部和侵入条件下对生态系统功能和食物网稳定性的影响。我们设计了几种建模方案，以模仿不同类型的顶级掠食者（专家/平民主义者）及其起源（本地/侵入性）的组合。我们的模型从理论上表明，顶级掠食者之间对猎物的较低开发竞争（具有较高的攻击率的独特猎物偏好）将有利于生态系统的功能和食物网的稳定性。我们还证明了顶级掠食者入侵的成功取决于本地和侵入性顶级掠食者的猎物偏好。对模型的敏感性分析进一步支持了我们的发现。我们的结果凸显了在控制多营养生态系统特性中，多个顶级捕食者对猎物的偏爱的重要性。我们的发现可能具有重要意义，因为当前不断发生的全球变化深刻地改变了许多生物系统的物候，并造成了营养失配，