de Mol Friederike, Fritzsche Robert, Gerowitt Bärbel
Faculty of Agricultural and Environmental Sciences, Crop Health, University of Rostock, Rostock, Germany.
Pest Manag Sci. 2025 Jul 29. doi: 10.1002/ps.70019.
Extensive herbicide use is one reason for the declining biodiversity of arable weeds. This study aimed to investigate (i) whether herbicide decisions recommended by a decision support system increase the weed species diversity compared to standard recommendations, and (ii) whether high weed species diversity reduces herbicide intensity, which in turn contributes to higher diversity. Data on weeds and herbicide applications in winter wheat fields in north-eastern Germany were collected in 15 field trials over 2 years. Five treatments differed in the way of decision-making for herbicide application, including two treatments according to recommendations of decision support systems.
Along the Hill's series biodiversity metrics, the untreated control had the highest species richness (13.5 m) per field but showed increasingly stronger dominance structures than the treated plots (equivalent species richness: 1.7-2.0 m). The treatment frequency index as a metric for herbicide intensity was significantly lowest in the decision support system with low reliability (1.07). Path models, including weed diversity and density in autumn, weed diversity in summer, and herbicide intensity as a mediating variable showed a significant decreasing effect of Shannon diversity on herbicide intensity in all treatments. Only the decision support systems reacted to low weed densities with a significant reduction of the herbicide intensity.
Higher weed species diversity contributes to lower herbicide intensity, which is ecologically and economically valuable. Decision support systems for herbicide application should have other target functions than cost reduction for contributing to biodiversity. © 2025 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
大量使用除草剂是导致农田杂草生物多样性下降的原因之一。本研究旨在调查：（i）与标准建议相比，决策支持系统推荐的除草剂决策是否能增加杂草物种多样性；（ii）高杂草物种多样性是否会降低除草剂使用强度，进而有助于提高生物多样性。在两年时间里，通过15个田间试验收集了德国东北部冬小麦田杂草和除草剂施用的数据。五种处理在除草剂施用决策方式上有所不同，其中包括根据决策支持系统建议的两种处理。
沿着希尔系列生物多样性指标，未处理的对照地块每块田的物种丰富度最高（13.5种），但与处理地块相比，其优势结构越来越强（等效物种丰富度：1.7 - 2.0种）。作为除草剂使用强度指标的处理频率指数在可靠性较低的决策支持系统中显著最低（1.07）。路径模型包括秋季杂草多样性和密度、夏季杂草多样性以及作为中介变量的除草剂使用强度，结果显示在所有处理中，香农多样性对除草剂使用强度均有显著的降低作用。只有决策支持系统会对低杂草密度做出反应，显著降低除草剂使用强度。
更高的杂草物种多样性有助于降低除草剂使用强度，这在生态和经济方面都具有重要价值。除草剂施用的决策支持系统除了降低成本外，还应有其他有助于生物多样性的目标功能。© 2025作者。由John Wiley & Sons Ltd代表化学工业协会出版的《害虫管理科学》。
