New publication from He et al. in Communications Biology: Cumulative nitrogen enrichment alters the drivers of grassland overyielding

Effects of plant diversity on grassland productivity, or overyielding, are found to be robust to nutrient enrichment. However, the impact of cumulative nitrogen (N) addition (total N added over time) on overyielding and its drivers are underexplored. Synthesizing data from 15 multi-year grassland biodiversity experiments with N addition, we found that N addition decreases complementarity effects and increases selection effects proportionately, resulting in no overall change in overyielding regardless of N addition rate. However, we observed a convex relationship between overyielding and cumulative N addition, driven by a shift from complementarity to selection effects. This shift suggests diminishing positive interactions and an increasing contribution of a few dominant species with increasing N accumulation. Recognizing the importance of cumulative N addition is vital for understanding its impacts on grassland overyielding, contributing essential insights for biodiversity conservation and ecosystem resilience in the face of increasing N deposition.

The impacts of nitrogen addition treatment on the relationships between
species richness and overyielding. The impacts ofNaddition on the relationships of
species richness with net biodiversity effects (a), complementarity effects (b) and selection effects (c). Black lines indicate fixed effects, and colored lines indicate
random effects. Note that the x-axes are on the log-2 scale, the y-axes are on the
original scale with unit g/m2/year.


He, M., K. E. Barry, M. B. Soons, E. Allan, S. L. Cappelli, et al. 2024. Cumulative nitrogen enrichment alters the drivers of grassland overyielding. Communications Biology 7:1–10.