Abstract
Quantifying the nitrogen (N) surplus (the difference between N inputs and outputs) of an agricultural system is crucial for improving N use efficiency and reducing its loss. The fates of surplus N during land-use change from cereals to apple orchards from 1990 to 2017 in Luochuan County on the Loess Plateau, were quantified. The ratio of apple orchard area to total agricultural land in the county increased from 18% in 1990 to 73% in 2017. As cereal lands were converted to apple orchards, the annual N input and N surplus of the total cereal-orchard system increased significantly from 161 kg N ha-1 and 58 kg N ha-1 in 1990 to 543 kg N ha-1 and 477 kg N ha-1 in 2017, respectively. The average nitrate accumulation in the 0–2 m and 0–6 m soil profiles reached 2635 kg N ha-1 and 5611 kg N ha-1, respectively, in 2017. Approximately 67% of the total N surpluses from 1990 to 2017 accumulated in the soil profile in the form of nitrate. This result highlights the role of nitrate accumulation in the vadose zone as the main fate of surplus N in the intensive agricultural landscape, which should be considered an important component of the soil N budget to optimize production and environmental protection.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
