title: Estimation and mitigation of N2O emission and nitrate leaching from intensive crop cultivation in the Haean catchment, South Korea.
abstract: Considering intensive agricultural management practices and environmental conditions, the LandscapeDNDC model was applied for simulation of yields, N2O emission and nitrate leaching from major upland crops and temperate deciduous forest of the Haean catchment, South Korea. Fertilization rates were high (up to 314 kg N ha(-1) year(-1)) and resulted in simulated direct N2O emissions from potato, radish, soybean and cabbage fields of 1.9 and 2.1 kg N ha(-1) year(-1) in 2009 and 2010, respectively. Nitrate leaching was identified as the dominant pathway of N losses in the Haean catchment with mean annual rates of 112.2 and 125.4 kg N ha(-1) year(-1), causing threats to water quality and leading to substantial indirect N2O emissions of 0.84 and 0.94 kg N ha(-1) year(-1) in 2009 and 2010 as estimates by applying the IPCC EF5. Simulated N2O emissions from temperate deciduous forest were low (approx. 0.50 kg N ha(-1) year(-1)) and predicted nitrate leaching rates were even negligible (≤0.01 kg N ha(-1) year(-1)). On catchment scale more than 50% of the total N2O emissions and up to 75% of nitrate leaching originated from fertilized upland fields, only covering 24% of the catchment area. Taking into account area coverage of simulated upland crops and other land uses these numbers agree well with nitrate loads calculated from discharge and concentration measurements at the catchment outlet. The change of current agricultural management practices showed a high potential of reducing N2O emission and nitrate leaching while maintaining current crop yields. Reducing (39%) and splitting N fertilizer application into 3 times was most effective and lead to about 54% and 77% reducing of N2O emission and nitrate leaching from the Haean catchment, the latter potentially contributing to improved water quality in the Soyang River Dam, which is the major source of drinking water for metropolitan residents.
authors.affiliation: Institute of Meteorology and Climate Research (IMK-IFU), Karlsruhe Institute of Technology, 82467 Garmisch-Partenkirchen, Germany; Department of Plant Ecology, University of Bayreuth, 95447 Bayreuth, Germany.
authors.forename: Youngsun
authors.initials: Y
authors.lastname: Kim
authors.affiliation: Gangwondo Agricultural Research and Extension Services, 200-150 Gangwon Province, Republic of Korea.
authors.forename: Youngho
authors.initials: Y
authors.lastname: Seo
authors.affiliation: Institute of Meteorology and Climate Research (IMK-IFU), Karlsruhe Institute of Technology, 82467 Garmisch-Partenkirchen, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Kraus
authors.affiliation: Institute of Meteorology and Climate Research (IMK-IFU), Karlsruhe Institute of Technology, 82467 Garmisch-Partenkirchen, Germany.
authors.forename: Steffen
authors.initials: S
authors.lastname: Klatt
authors.affiliation: Institute of Meteorology and Climate Research (IMK-IFU), Karlsruhe Institute of Technology, 82467 Garmisch-Partenkirchen, Germany.
authors.forename: Edwin
authors.initials: E
authors.lastname: Haas
authors.affiliation: Department of Plant Ecology, University of Bayreuth, 95447 Bayreuth, Germany.
authors.forename: John
authors.initials: J
authors.lastname: Tenhunen
authors.affiliation: Institute of Meteorology and Climate Research (IMK-IFU), Karlsruhe Institute of Technology, 82467 Garmisch-Partenkirchen, Germany. Electronic address: ralf.kiese@kit.edu.
authors.forename: Ralf
authors.initials: R
authors.lastname: Kiese
mesh_terms: D000383:Agriculture; D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000517:prevention & control / Q000706:statistics & numerical data*; D018556:Crops, Agricultural; D004784:Environmental Monitoring; D005308:Fertilizers; D009585:Nitrogen Dioxide / Q000032:analysis*; D056910:Republic of Korea
chemical_list: D000393:Air Pollutants; D005308:Fertilizers; D009585:Nitrogen Dioxide
keywords: LandscapeDNDC; Mitigation strategies; N(2)O; Nitrate leaching; Water quality