Biodiversity effects on ecosystem functioning in a 15-year grassland experiment: Patterns, mechanisms, and open questions
Overyielding (mixtures outperforming best monoculture) appeared in 96% of diverse plots
This comprehensive analysis of the Jena Experiment in Germany provides crucial evidence for functional complementarity and ecosystem multifunctionality. The Jena Experiment planted grassland plots with 1 to 60 species and measured productivity, nutrient retention, and resistance to drought, flood, and herbivory.
Key findings cited in the chapter: overyielding appeared in 96% of diverse plots, diverse plots rooted 30% deeper, bloomed across more months, and captured 40% more nitrogen than monocultures. This demonstrates that diversity increases total function through niche complementarity, not just buffering variance.
The research also supports the ecosystem multifunctionality concept: plots with 16+ species maintained high levels of 12+ ecosystem functions simultaneously, while no low-diversity plot achieved high multifunctionality.
Key Findings from Weisser et al. (2017)
- Overyielding (mixtures outperforming best monoculture) appeared in 96% of diverse plots
- Diverse plots rooted 30% deeper than monocultures
- Diverse plots captured 40% more nitrogen than monocultures
- Plots with 16+ species maintained high levels of 12+ functions simultaneously
- No monoculture or low-diversity plot achieved high multifunctionality