Modelling nitrogen flows in peri-urban vegetable field plots in Nanjing, China
Many parts of China are going through a rapid development and urbanization resulting in various environmental impairities. The Yangtze Delta Region surface water bodies are affected by eutrophication, partly caused by diffuse losses from agriculture. In this study, nitrogen, and to some extent al...
| Autor principal: | |
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| Formato: | Otro |
| Lenguaje: | sueco Inglés |
| Publicado: |
2005
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| Materias: | |
| Acceso en línea: | https://stud.epsilon.slu.se/11860/ |
| _version_ | 1855571954669453312 |
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| author | Berg, Josefin |
| author_browse | Berg, Josefin |
| author_facet | Berg, Josefin |
| author_sort | Berg, Josefin |
| collection | Epsilon Archive for Student Projects |
| description | Many parts of China are going through a rapid development and urbanization resulting
in various environmental impairities. The Yangtze Delta Region surface water bodies
are affected by eutrophication, partly caused by diffuse losses from agriculture. In this
study, nitrogen, and to some extent also phosphorus, flows and losses from two plots in
an intensively cultivated vegetable field in a peri-urban area of Nanjing, with a high
input of organic fertilizer, were analysed by the use of the field-scale simulation model
GLEAMS. The GLEAMS model was parameterized and calibrated against measurements of soil water and nitrogen content in two plots. A scenario with a reduced input of nitrogen was then simulated.
The resemblance between simulated and measured water content in the different soil
layers was quite poor. The simulated inorganic nitrogen content in the soil was
significantly lower than the measured during great parts of the simulation period. This
could be due to an inappropriate simulation of the mineralization of organic N under
these conditions, or an underestimated decomposition rate of manure. It is also possible
that the poor water simulations contributed to the underestimated inorganic N content in
the soil. There were similar results for the two plots, except for an unexplained 20%
increase in leaching and erosion losses of N in Plot B. For simulation of scenarios to
find best management practices, the model parameterization should be further refined. |
| format | Otro |
| id | RepoSLU11860 |
| institution | Swedish University of Agricultural Sciences |
| language | Swedish Inglés |
| publishDate | 2005 |
| publishDateSort | 2005 |
| record_format | eprints |
| spelling | RepoSLU118602024-07-10T09:13:08Z https://stud.epsilon.slu.se/11860/ Modelling nitrogen flows in peri-urban vegetable field plots in Nanjing, China Berg, Josefin Dept. of Soil Sciences Soil chemistry and physics Many parts of China are going through a rapid development and urbanization resulting in various environmental impairities. The Yangtze Delta Region surface water bodies are affected by eutrophication, partly caused by diffuse losses from agriculture. In this study, nitrogen, and to some extent also phosphorus, flows and losses from two plots in an intensively cultivated vegetable field in a peri-urban area of Nanjing, with a high input of organic fertilizer, were analysed by the use of the field-scale simulation model GLEAMS. The GLEAMS model was parameterized and calibrated against measurements of soil water and nitrogen content in two plots. A scenario with a reduced input of nitrogen was then simulated. The resemblance between simulated and measured water content in the different soil layers was quite poor. The simulated inorganic nitrogen content in the soil was significantly lower than the measured during great parts of the simulation period. This could be due to an inappropriate simulation of the mineralization of organic N under these conditions, or an underestimated decomposition rate of manure. It is also possible that the poor water simulations contributed to the underestimated inorganic N content in the soil. There were similar results for the two plots, except for an unexplained 20% increase in leaching and erosion losses of N in Plot B. For simulation of scenarios to find best management practices, the model parameterization should be further refined. Den snabba utvecklingen och urbaniseringen i stora delar av Kina har ett flertal konsekvenser för miljön. Yangtzedeltats ytvatten är till stor del eutrofierade, delvis p.g.a. diffusa förluster från jordbruket. I denna studie har kväve- och, till viss del, fosforflöden och förluster från två odlingsrutor i ett intensivt odlat grönsaksfält i ett tätortsnära område i Nanjing, med hög tillförsel av organiskt gödsel, undersökts med hjälp av den fältskaliga simuleringsmodellen GLEAMS. GLEAMS parametriserades och kalibrerades mot mätvärden av jordens vatten- och kväveinnehåll. Ett scenario med minskad kvävetillförsel simulerades sedan. Simuleringen av vattenhalten i de olika horisonterna var inte utmärkt. Den simulerade mängden mineralkväve i marken var avsevärt lägre än den uppmätta. Detta kan bero på en felaktig simulering av mineraliseringen av organiskt kväve eller en för långsam nedbrytning av gödsel. Det är också möjligt att felen i vattensimuleringarna bidrog till underskattningen av mängden mineralkväve i marken. Simuleringarna på de båda odlingsrutorna gav liknande resultat, förutom att ruta B hade 20% större förluster av N via simulerad erosion och läckage. För fortsatt simulering av alternativa odlingsmetoder bör modellens parametrisering förbättras, särskilt vad avser parametrar kopplade till gödselns mineralisering. 2005-12-22 Other NonPeerReviewed application/pdf sv https://stud.epsilon.slu.se/11860/1/berg_j_171013.pdf Berg, Josefin, 2005. Modelling nitrogen flows in peri-urban vegetable field plots in Nanjing, China. UNSPECIFIED, Uppsala. Uppsala: (NL, NJ) > Dept. of Soil Sciences <https://stud.epsilon.slu.se/view/divisions/4023.html> urn:nbn:se:slu:epsilon-s-7813 eng |
| spellingShingle | Dept. of Soil Sciences Soil chemistry and physics Berg, Josefin Modelling nitrogen flows in peri-urban vegetable field plots in Nanjing, China |
| title | Modelling nitrogen flows in peri-urban vegetable field plots in Nanjing, China |
| title_full | Modelling nitrogen flows in peri-urban vegetable field plots in Nanjing, China |
| title_fullStr | Modelling nitrogen flows in peri-urban vegetable field plots in Nanjing, China |
| title_full_unstemmed | Modelling nitrogen flows in peri-urban vegetable field plots in Nanjing, China |
| title_short | Modelling nitrogen flows in peri-urban vegetable field plots in Nanjing, China |
| title_sort | modelling nitrogen flows in peri-urban vegetable field plots in nanjing, china |
| topic | Dept. of Soil Sciences Soil chemistry and physics |
| url | https://stud.epsilon.slu.se/11860/ https://stud.epsilon.slu.se/11860/ |