Toggle Main Menu Toggle Search

Open Access padlockePrints

The Effects of Nitrogen Fertilisation on Plant Species Richness in European Permanent Grasslands: A Systematic Review and Meta-Analysis

Lookup NU author(s): Dr Richard Francksen, Dr Caroline Rhymer, Dr Gavin Stewart, Professor Mark WhittinghamORCiD



This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).


© 2022 by the authors.Nitrogen fertilisation is a common form of agricultural intensification, aimed at increasing biomass, which can affect plant species diversity and ecosystem functioning. Using a systematic review and meta-analysis of nitrogen fertilisation studies in European permanent grasslands, we asked: (i) what relationship form exists between nitrogen application rate and change in plant diversity, compared to zero fertilisation controls; and (ii) how grassland, management and study characteristics affect this relationship. Meta-analysis of 34 control-treatment effects from 14 studies conducted across nine European countries revealed a negative linear relationship between nitrogen fertilisation rate and change in plant species richness, equivalent to approximately 1.5 species/m2 lost for every 100 Kg ha−1 yr−1 of nitrogen added. Fertilisation induced reductions in plant species richness were greater when defoliation rates were lower. We found some evidence that grasslands with a higher baseline plant diversity lost more species when fertilised compared to more species poor grasslands, although uncertainty was high. Due to the diverse grassland types included in the analysis, the variability in fertilisation-driven changes in plant diversity was high. We identified several remaining limitations to our understanding, including uncertainty about non-linear effects, which could aid efforts to optimise the trade-off of plant diversity and increasing grassland yields.

Publication metadata

Author(s): Francksen RM, Turnbull S, Rhymer CM, Hiron M, Bufe C, Klaus VH, Newell-Price P, Stewart G, Whittingham MJ

Publication type: Review

Publication status: Published

Journal: Agronomy

Year: 2022

Volume: 12

Issue: 12

Online publication date: 23/11/2022

Acceptance date: 22/11/2022

ISSN (electronic): 2073-4395

Publisher: MDPI


DOI: 10.3390/agronomy12122928