Plants compete for the same resources, such as nutrients, light and water. Because these resources are often limited, the coexistence of plant species requires the creation of trade-offs in resource use. In this issue, Harpole et al. report that increasing a limited nutrient in grassland can eliminate these potential trade-offs, reducing overall species diversity (W. S. Harpole et al. Nature 537, 93–96; 2016).
The authors considered 45 grassland sites across 6 continents, and measured species diversity in response to various nutrient additions. Their results provide strong evidence for a broad ecological theory — that the availability of multiple limiting resources allows plants with different limiting requirements to coexist.
The greater the number of limiting resources that were added, the more species were lost, although productivity and turnover improved. The researchers argue that, by understanding the mechanisms by which diversity is lost, we might develop strategies for restoring and preserving Earth's biodiversity. Footnote 1
About this article
Cite this article
Wilkinson, R. More is less. Nature 537, 42 (2016). https://doi.org/10.1038/537042a