Abstract

Nitrogen (N) fertilisation has positive and negative effects on the environmental impact of crop cultivation. The mechanisms governing these effects are highly site-dependent, a factor often ignored in assessments of the environmental impact of crop cultivation. By assessing outputs of crop rotations using a life cycle approach, this study explored how greenhouse gas emissions and marine eutrophication caused by crop cultivation (including upstream processes such as production of farm inputs) depend on fertiliser rate and the site at which the cultivation occurs. Cereal unit (CU) was used as the functional unit. The calculations were based on data from multi-site long-term field experiments in Sweden and site-dependent data and models for non-measured processes. Cultivation at three N levels was evaluated, where the highest N rate was close to current average practices and the lowest level corresponded to one-third of that. Site characteristics had a stronger influence on both greenhouse gas emissions and marine eutrophication (variations of up to 330% and 490%, respectively, within N levels) than N level (variations of up to 74% and 59%, respectively, within sites). Main sources of variation in greenhouse gas emissions were soil nitrous oxide emissions (58-810g CO2eqCU-1) and soil organic carbon changes (14-720g CO2eqCU-1), while variations in marine eutrophication were mainly explained by field-level waterborne N losses (0.9-8.2g NeqCU-1). The large variation between sites highlights the importance of considering site characteristics when assessing the environmental impact of crop cultivation and evaluating the environmental consequences of crop management practices.

Keywords

Environmental impact; Life cycle assessment; Eutrophication; Climate impact; Greenhouse gas emissions; Site-dependent

Published in

Nutrient cycling in agroecosystems
2019, Volume: 114, number: 2, pages: 139-155
Publisher: SPRINGER

SLU Authors

• Henryson, Kajsa

  • Department of Energy and Technology, Swedish University of Agricultural Sciences
    

• Hansson, Per-Anders

  • Department of Energy and Technology, Swedish University of Agricultural Sciences
    

• Kätterer, Thomas

  • Department of Ecology, Swedish University of Agricultural Sciences
    

• Tidåker, Pernilla

  • Department of Energy and Technology, Swedish University of Agricultural Sciences
    

• Sundberg, Cecilia

  • Department of Energy and Technology, Swedish University of Agricultural Sciences
    
  • Royal Institute of Technology (KTH)

Sustainable Development Goals

Ensure sustainable consumption and production patterns


UKÄ Subject classification

Environmental Sciences related to Agriculture and Land-use


Publication identifier

DOI: https://doi.org/10.1007/s10705-019-09997-w

Permanent link to this page (URI)

https://res.slu.se/id/publ/100403