Department of Ecology and Evolutionary Biology, University of California Irvine, Irvine, California, USA.
Misión Biológica de Galicia, Consejo Superior de Investigaciones Científicas (MBG-CSIC), Pontevedra, España.
Ecol Lett. 2024 May;27(5):e14427. doi: 10.1111/ele.14427.
Tree diversity can promote both predator abundance and diversity. However, whether this translates into increased predation and top-down control of herbivores across predator taxonomic groups and contrasting environmental conditions remains unresolved. We used a global network of tree diversity experiments (TreeDivNet) spread across three continents and three biomes to test the effects of tree species richness on predation across varying climatic conditions of temperature and precipitation. We recorded bird and arthropod predation attempts on plasticine caterpillars in monocultures and tree species mixtures. Both tree species richness and temperature increased predation by birds but not by arthropods. Furthermore, the effects of tree species richness on predation were consistent across the studied climatic gradient. Our findings provide evidence that tree diversity strengthens top-down control of insect herbivores by birds, underscoring the need to implement conservation strategies that safeguard tree diversity to sustain ecosystem services provided by natural enemies in forests.
树木多样性可以促进捕食者的丰富度和多样性。然而，这种多样性是否会转化为捕食者在不同分类群和对比环境条件下对食草动物的增加捕食和自上而下的控制，仍未得到解决。我们利用一个跨越三大洲和三个生物群落的全球树木多样性实验网络（TreeDivNet），测试了在不同温度和降水气候条件下，树木物种丰富度对捕食的影响。我们记录了在单一栽培和树木物种混合体中塑料质毛毛虫上的鸟类和节肢动物捕食尝试。树木物种丰富度和温度都增加了鸟类的捕食，但对节肢动物没有影响。此外，树木物种丰富度对捕食的影响在研究的气候梯度上是一致的。我们的研究结果提供了证据表明，树木多样性增强了鸟类对昆虫食草动物的自上而下的控制，这突显了实施保护策略以保护树木多样性来维持森林中天敌提供的生态系统服务的必要性。
