Science Advances Vol 12, Issue 30, https://doi.org/10.1126/sciadv.aeb8680
Involved members of MultiTroph: Helge Bruelheide, Jing-Ting Chen, Yi Li, Jana Petermann, Andreas Schuldt, Michael Staab, Ming-Qiang Wang, Chao-Dong Zhu
Summary: For this study, data from 149 field studies across five continents were analyzed to examine how increasing plant diversity affects interactions between plants, herbivores, and their natural enemies in agricultural and natural ecosystems. The researchers found that plant diversity had different effects depending on the ecosystem. In croplands, greater plant diversity substantially increased the ratio of natural enemies to herbivores, indicating stronger top-down control of pests. In contrast, grasslands and forests showed bottom-up effects, where higher plant diversity increased the abundance of both herbivores and their predators through greater ecosystem productivity.
Conclusion: The ecological effects of plant diversity depend on ecosystem type and management practices. While increased plant diversity in natural ecosystems primarily supports higher productivity across multiple trophic levels, in agricultural systems it strengthens natural pest control by favoring predators over herbivores.