State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
University of Queensland, Brisbane, Queensland, Australia.
Commun Biol. 2021 Aug 18;4(1):979. doi: 10.1038/s42003-021-02509-z.
Land-use change and agricultural intensification concurrently impact natural enemy (e.g., parasitoid) communities and their associated ecosystem services (ESs), i.e., biological pest control. However, the extent to which (on-farm) parasitoid diversity and food webs mediate landscape-level influences on biological control remains poorly understood. Here, drawing upon a 3-year study of quantitative parasitoid-hyperparasitoid trophic networks from 25 different agro-landscapes, we assess the cascading effects of landscape composition, species diversity and trophic network structure on ecosystem functionality (i.e., parasitism, hyperparasitism). Path analysis further reveals cascaded effects leading to biological control of a resident crop pest, i.e., Aphis gossypii. Functionality is dictated by (hyper)parasitoid diversity, with its effects modulated by food web generality and vulnerability. Non-crop habitat cover directly benefits biological control, whereas secondary crop cover indirectly lowers hyperparasitism. Our work underscores a need to simultaneously account for on-farm biodiversity and trophic interactions when investigating ESs within dynamic agro-landscapes.
土地利用变化和农业集约化同时影响天敌（例如，寄生蜂）群落及其相关的生态系统服务（ES），即生物防治。然而，（农田）寄生蜂多样性和食物网在多大程度上调节景观水平对生物防治的影响仍知之甚少。在这里，我们利用了一项为期 3 年的、来自 25 个不同农业景观的定量寄生蜂-重寄生蜂营养网络的研究，评估了景观组成、物种多样性和营养网络结构对生态系统功能（即寄生、重寄生）的级联效应。路径分析进一步揭示了导致驻留作物害虫（即棉蚜）生物防治的级联效应。功能由（超）寄生蜂多样性决定，其效应受食物网一般性和脆弱性调节。非作物生境覆盖直接有利于生物防治，而次生作物覆盖间接降低重寄生作用。我们的工作强调了在动态农业景观中研究 ES 时，需要同时考虑农田生物多样性和营养相互作用。
