Ecosystem C and N dynamics affected by a modified spring barley trait with increased nitrogen use - a simulation case study. (3rd April 2018)

• Record Type: Journal Article
• Authors: Eckersten, Henrik; Marstorp, Håkan; Collentine, Dennis; Johnsson, Holger; Kätterer, Thomas
• Is Part Of: Acta agriculturæ Scandinavica. Volume 68:Number 3(2018)
• Page Start: 230
• Page End: 242
• Publication Date: 2018-04-03
• Subjects: Plant breeding -- N uptake -- N utilisation -- N leaching -- SOC -- sandy loam -- Sweden; Horticulture -- Periodicals; Soil science -- Periodicals; Crops and soils -- Periodicals; Plant-soil relationships -- Periodicals; 630
• DOI: 10.1080/09064710.2017.1385835
• Languages: English
• ISSNs: 0906-4710

Abstract

ABSTRACT: To what extent might a crop with increased plant N uptake efficiency and/or N demand increase plant biomass and soil carbon storage, decrease N leaching, and reduce the need for N fertilisation? This was assessed for a fertilised sandy loam site in central Sweden cultivated with spring barley for a four year period using a process based crop and soil simulation model (SOILN) calibrated to fit observations of field experiments with non-modified crops. Crop properties were changed in accordance with previous model applications to other crops with higher N uptake and utilisation efficiencies, to resemble potential effects of breeding. For the modified crops a doubling of daily uptake efficiency of soil mineral N and/or increase of radiation use efficiency by 30%, increased plant biomass by 3%–30%, decreased N leaching by 1%–30% and increased soil organic carbon (SOC) content by 1–12 g C m −2 year −1 . The larger changes were mainly due to increased uptake efficiency. Fertilisation of the modified spring barley crop could be reduced while still producing the same plant biomass as the non-modified crop. The plant biomass to N leaching ratio of the modified crops increased. The simulated changes in plant biomass and SOC were sensitive to weather conditions suggesting that in situ experiments would need to cover a large range of weather conditions to evaluate the performance of new crop traits under climatic variability. The study suggests a strong need that field experiments are accompanied with model applications, when exploring the potential of the modified crops under variable conditions.