title: Tradeoffs between Maize Silage Yield and Nitrate Leaching in a Mediterranean Nitrate-Vulnerable Zone under Current and Projected Climate Scenarios.
abstract: Future climatic changes may have profound impacts on cropping systems and affect the agronomic and environmental sustainability of current N management practices. The objectives of this work were to i) evaluate the ability of the SALUS crop model to reproduce experimental crop yield and soil nitrate dynamics results under different N fertilizer treatments in a farmer's field, ii) use the SALUS model to estimate the impacts of different N fertilizer treatments on NO3- leaching under future climate scenarios generated by twenty nine different global circulation models, and iii) identify the management system that best minimizes NO3- leaching and maximizes yield under projected future climate conditions. A field experiment (maize-triticale rotation) was conducted in a nitrate vulnerable zone on the west coast of Sardinia, Italy to evaluate N management strategies that include urea fertilization (NMIN), conventional fertilization with dairy slurry and urea (CONV), and no fertilization (N0). An ensemble of 29 global circulation models (GCM) was used to simulate different climate scenarios for two Representative Circulation Pathways (RCP6.0 and RCP8.5) and evaluate potential nitrate leaching and biomass production in this region over the next 50 years. Data collected from two growing seasons showed that the SALUS model adequately simulated both nitrate leaching and crop yield, with a relative error that ranged between 0.4% and 13%. Nitrate losses under RCP8.5 were lower than under RCP6.0 only for NMIN. Accordingly, levels of plant N uptake, N use efficiency and biomass production were higher under RCP8.5 than RCP6.0. Simulations under both RCP scenarios indicated that the NMIN treatment demonstrated both the highest biomass production and NO3- losses. The newly proposed best management practice (BMP), developed from crop N uptake data, was identified as the optimal N fertilizer management practice since it minimized NO3- leaching and maximized biomass production over the long term.
authors.affiliation: Department of Geological Sciences and W.K. Kellogg Biological Station, Michigan State University, East Lansing, MI, United States of America.
authors.forename: Bruno
authors.initials: B
authors.lastname: Basso
authors.affiliation: Sezione di Scienze Agronomiche, Coltivazioni Erbacee e Genetica (SACEG), Dipartimento di Agraria, Università di Sassari, Sassari, Italy.
authors.forename: Pietro
authors.initials: P
authors.lastname: Giola
authors.affiliation: Department of Geological Sciences and W.K. Kellogg Biological Station, Michigan State University, East Lansing, MI, United States of America.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Dumont
authors.affiliation: Institute of Future Environment, Queensland University of Technology, Brisbane, QLD, Australia.
authors.forename: Massimiliano De Antoni
authors.initials: Mde A
authors.lastname: Migliorati
authors.affiliation: James Hutton Institute, Invergowrie, Dundee, DD2 5DA, Scotland, United Kingdom.
authors.forename: Davide
authors.initials: D
authors.lastname: Cammarano
authors.affiliation: Sezione di Scienze Agronomiche, Coltivazioni Erbacee e Genetica (SACEG), Dipartimento di Agraria, Università di Sassari, Sassari, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Pruneddu
authors.affiliation: Sezione di Scienze Agronomiche, Coltivazioni Erbacee e Genetica (SACEG), Dipartimento di Agraria, Università di Sassari, Sassari, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Giunta
mesh_terms: D018533:Biomass; D057231:Climate Change; D018556:Crops, Agricultural / Q000187:drug effects / Q000254:growth & development*; D005308:Fertilizers / Q000009:adverse effects; D019083:Mediterranean Region; D009566:Nitrates / Q000009:adverse effects / Q000032:analysis*; D058458:Nitrogen Cycle; D003313:Zea mays / Q000187:drug effects / Q000254:growth & development*
chemical_list: D005308:Fertilizers; D009566:Nitrates