Nutrient enrichment can simultaneously increase and destabilise plant biomass production, with co-limitation by multiple nutrients potentially intensifying these effects. Here, we test how factorial additions of nitrogen (N), phosphorus (P) and potassium with essential nutrients (K+) affect the stability (mean/standard deviation) of aboveground biomass in 34 grasslands over 7 years. Destabilisation with fertilisation was prevalent but was driven by single nutrients, not synergistic nutrient interactions. On average, N-based treatments increased mean biomass production by 21–51% but increased its standard deviation by 40–68% and so consistently reduced stability. Adding P increased interannual variability and reduced stability without altering mean biomass, while K+ had no general effects. Declines in stability were largest in the most nutrient-limited grasslands, or where nutrients reduced species richness or intensified species synchrony. We show that nutrients can differentially impact the stability of biomass production, with N and P in particular disproportionately increasing its interannual variability.
This is the peer reviewed version of the following article:Carroll, O., Batzer, E., Bharath, S., Borer, E.T., Campana, S., Esch, E., et al. (2022) Nutrient identity modifies the destabilising effects of eutrophication in grasslands. Ecology Letters, 25, 754– 765. Available from: https://doi.org/10.1111/ele.13946 which has been published in final form at https://onlinelibrary.wiley.com/doi/10.1111/ele.13946 This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving.