Landscape-level crop diversity benefits biological pest control

1.Landscape-level crop diversification is a promising tool for ecological intensification, whereby biodiversity and ecosystem services are enhanced, and pesticide applications reduced. Yet evidence for the effects of crop diversity at multiple scales and in different landscape contexts is lacking. Here, we investigate the potential benefits and context-dependencies of multiscale crop diversity on natural enemies and overall biological control in winter wheat. Simultaneously, we examine the mediating effects of bird predation on aphid regulation in this system.

2.Eighteen conventional winter wheat fields were selected along two independent gradients of crop diversity and seminatural habitat cover (SNH). We assessed biological control using a natural enemy exclusion experiment (‘Open Treatment’, ‘Bird Exclosure’, ‘Full Exclosure’). Biological control, predator and parasitoid densities within cages were analysed as functions of landscape (crop diversity x SNH), bird predation (yes/no) a...

1. 景观尺度下的作物多样性是生态集约化（ecological intensification）的颇具潜力的实施路径，可提升生物多样性（biodiversity）与生态系统服务（ecosystem services），并减少农药施用（pesticide applications）。然而目前学界仍缺乏作物多样性在多尺度及不同景观背景下的效应相关研究。本研究以冬小麦（winter wheat）农田生态系统为研究对象，探究多尺度作物多样性对天敌（natural enemies）类群及整体生物防治（biological control）的潜在效益与情境依赖性；同时分析鸟类捕食（bird predation）在该系统中对蚜虫调控（aphid regulation）的中介效应。
2. 本研究沿作物多样性与半自然生境覆盖度（SNH）两条独立梯度，选取了18块常规冬小麦田。本研究通过天敌排除实验（natural enemy exclusion experiment）评估生物防治效果，实验设置包括「开放处理组（Open Treatment）」、「鸟类排除组（Bird Exclosure）」与「完全排除组（Full Exclosure）」。以笼网内的生物防治效应、捕食者与寄生蜂密度为因变量，分析其与景观因子（作物多样性×半自然生境覆盖度）、鸟类捕食（存在/缺失）的关联……