Agricultural production in the EU has increased strongly since the 1940s, partly driven by increased nitrogen (N) fertiliser and manure inputs. Increased N inputs and associated losses, however, adversely affect air and water quality, with widespread impacts on terrestrial and aquatic ecosystems and human health. Managing these impacts requires knowledge on 'safe boundaries' for N inputs, i.e., N flows that do not exceed environmental thresholds. We used a spatially explicit N balance model for the EU to derive boundaries for N losses and associated N inputs for three environmental thresholds: (i) N deposition onto natural areas to protect terrestrial biodiversity (critical N loads), (ii) N concentration in runoff to surface water (2.5 mg N l-1) to protect aquatic ecosystems and (iii) nitrate (NO3-) concentration in leachate to groundwater (50 mg NO l-1) to meet the EU drinking water standard. Critical N losses and inputs were calculated for ~40,000 unique soil-slope-climate combinations and then aggregated at country- and EU-level. To respect thresholds for N deposition, N inputs in the EU need to be reduced by 31% on average, ranging from 0% in several countries to 59% in Ireland and Denmark. The strongest reductions are required in intensive livestock regions, such as Benelux, Brittany and the Po valley. To respect thresholds for N concentration in runoff to surface water, N inputs need to be reduced by 43% on average, ranging from 2% in Estonia to 74% in the Netherlands. Average critical N inputs in view of the threshold for NO3- concentration in leachate to groundwater are close to actual (year 2010) inputs, even though leaching thresholds are exceeded in 18% of agricultural land. Critical N inputs and their exceedances presented in this paper can inform more targeted mitigation policies than flat-rate targets for N loss reductions currently mentioned in EU policies.
Spatially explicit boundaries for agricultural nitrogen inputs in the European Union to meet air and water quality targets.
W. de Vries,L. Schulte-Uebbing,H. Kros,J. Voogd,G. Louwagie
Published 2021 in Science of the Total Environment
ABSTRACT
PUBLICATION RECORD
- Publication year
2021
- Venue
Science of the Total Environment
- Publication date
2021-04-23
- Fields of study
Agricultural and Food Sciences, Medicine, Environmental Science
- Identifiers
- External record
- Source metadata
Semantic Scholar, PubMed
CITATION MAP
EXTRACTION MAP
CLAIMS
- No claims are published for this paper.
CONCEPTS
- No concepts are published for this paper.
REFERENCES
Showing 1-24 of 24 references · Page 1 of 1