Water balance and nitrate leaching from arable land in a changed climate
This thesis aims to present the essential background on how to perform climate change impact assessments, and to present the results from a climate impact assessment on water balance and nitrate leaching for an arable Swedish soil. The soil is a sandy soil in southwestern Sweden, grown with spring c...
| Autor principal: | |
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| Formato: | Second cycle, A1E |
| Lenguaje: | sueco Inglés |
| Publicado: |
2011
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| Materias: | |
| Acceso en línea: | https://stud.epsilon.slu.se/3362/ |
| _version_ | 1855570557580345344 |
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| author | Nanos, Therése |
| author_browse | Nanos, Therése |
| author_facet | Nanos, Therése |
| author_sort | Nanos, Therése |
| collection | Epsilon Archive for Student Projects |
| description | This thesis aims to present the essential background on how to perform climate change
impact assessments, and to present the results from a climate impact assessment on water
balance and nitrate leaching for an arable Swedish soil. The soil is a sandy soil in southwestern
Sweden, grown with spring cereals. This study is meant to be a benchmark example,
and cannot be seen as a regional or national assessment for Sweden, rather as an approach
to present and analyze the most important parts of these kinds of assessments.
A dynamical simulation model (COUP, Jansson and Karlberg, 2004) was used for this
study. The model was parameterized and calibrated against data from an experimental site,
located in Mellby in Hallands county, south western Sweden. Measurements were carried
out between 1st of April 1988 and 1st of April 1991. The data set consists of daily standard
weather data and discharge, data on soil water content, soil nitrogen and nitrogen contents
in drainage water from to experimental fields grown with spring cereals. The model was
calibrated against the 4-year data set based on a GLUE-procedure in which a number of
“acceptable parameter sets” were identified. One of these parameter sets were randomly
chosen for the climate impact model runs performed in this study. The driving data for the
model are 30-year climate data, including data for precipitation, temperature, solar radiation,
relative humidity and wind speed, which enables long-term simulations of water and
nitrogen flows. Three different simulations were performed, one for present climate as a
reference scenario with climate data from 1971-2000, and two different emission scenarios
representing year 2071-2100. The driving data were constructed by the delta-change method,
which is a common way of interfacing regional climate model output with impact
models.
Results show that, for both scenarios, that nitrate leaching will increase with 41 % and
66 % respectively. This is mainly due to increased winter temperatures (increasing nitrogen
mineralization with 22 % and 32 % respectively) and increased drainage (20 % and 33
% respectively) during the period when the soil is left bare.
It is important to remember that the study includes many generalizations, both in parameterization
and in driving data. Despite that, the approach with a dynamical model driven
with long-term climate data is a very robust and valuable way of making such assessments.
Further studies need to consider crop growth characteristics and crop parameterization to
be able to simulate growth of other varieties more suitable in a changed climate. Ensemble
modeling can also be an approach to reduce biases in the modeling chain. |
| format | Second cycle, A1E |
| id | RepoSLU3362 |
| institution | Swedish University of Agricultural Sciences |
| language | swe Inglés |
| publishDate | 2011 |
| publishDateSort | 2011 |
| record_format | eprints |
| spelling | RepoSLU33622012-04-20T14:22:58Z https://stud.epsilon.slu.se/3362/ Water balance and nitrate leaching from arable land in a changed climate Nanos, Therése Soil science and management This thesis aims to present the essential background on how to perform climate change impact assessments, and to present the results from a climate impact assessment on water balance and nitrate leaching for an arable Swedish soil. The soil is a sandy soil in southwestern Sweden, grown with spring cereals. This study is meant to be a benchmark example, and cannot be seen as a regional or national assessment for Sweden, rather as an approach to present and analyze the most important parts of these kinds of assessments. A dynamical simulation model (COUP, Jansson and Karlberg, 2004) was used for this study. The model was parameterized and calibrated against data from an experimental site, located in Mellby in Hallands county, south western Sweden. Measurements were carried out between 1st of April 1988 and 1st of April 1991. The data set consists of daily standard weather data and discharge, data on soil water content, soil nitrogen and nitrogen contents in drainage water from to experimental fields grown with spring cereals. The model was calibrated against the 4-year data set based on a GLUE-procedure in which a number of “acceptable parameter sets” were identified. One of these parameter sets were randomly chosen for the climate impact model runs performed in this study. The driving data for the model are 30-year climate data, including data for precipitation, temperature, solar radiation, relative humidity and wind speed, which enables long-term simulations of water and nitrogen flows. Three different simulations were performed, one for present climate as a reference scenario with climate data from 1971-2000, and two different emission scenarios representing year 2071-2100. The driving data were constructed by the delta-change method, which is a common way of interfacing regional climate model output with impact models. Results show that, for both scenarios, that nitrate leaching will increase with 41 % and 66 % respectively. This is mainly due to increased winter temperatures (increasing nitrogen mineralization with 22 % and 32 % respectively) and increased drainage (20 % and 33 % respectively) during the period when the soil is left bare. It is important to remember that the study includes many generalizations, both in parameterization and in driving data. Despite that, the approach with a dynamical model driven with long-term climate data is a very robust and valuable way of making such assessments. Further studies need to consider crop growth characteristics and crop parameterization to be able to simulate growth of other varieties more suitable in a changed climate. Ensemble modeling can also be an approach to reduce biases in the modeling chain. Syftet med den här studien är att presentera bakgrunden till hur klimatförändringarnas potentiella effekter på mark-växt-systemet kan uppskattas, samt resultat från en modellstudie av klimatförändringens effekter på vattenbalans och nitratutlakning från en svensk jordbruksmark odlad med vårkorn.. Denna studie syftar till att vara ett exempel, och det är inte inom studiens ramar att fungera som ett regionalt eller nationellt underlag för hur nitratutlakningen in Sverige påverkas av ett föränderligt klimat. En dynamisk simuleringsmodell (COUP, Jansson och Karlberg, 2004), har använts i studien. Modellen är parameteriserad och kalibrerad mot data från ett fyra-årigt försök vid mätstationen i Mellby, Hallands län, sydvästra Sverige. Ett antal acceptabla parameter-set identifierades baserat på GLUE-metoden och ett av dessa valdes slumpmässigt ut för denna studie. Drivdata till modellen är 30-åriga klimatdata, innehållande daglig information om nederbörd, temperatur, sol instrålning, relativ fuktighet och vindhastighet. Dessa data möjliggör långtids simuleringar av vatten och kväveflöden i marken med daglig utdata. Tre scenarier användes för att studera klimatförändringens effekter, ett referens scenario som motsvarar dagens klimat mellan 1971-2000, samt två olika klimatscenarier som motsvarar åren 2071-2100. Drivdata-seten konstruerades med hjälp av den så kallade ”delta-change” - metoden, vilket är en metod för att transformera utdata från regionala klimatmodeller (RCM) till drivdata för platsspecifika modeller. Resultaten visar ökat läckage av nitratkväve för båda klimatscenarierna (41 % och 66 % från års medelvärde). Detta berodde huvudsakligen på ökad nederbörd samt ökat temperatur under vinterhalvåret, då marken är obevuxen. Netto mineraliseringen ökade med 22 % och 32 % respektive, och dräneringen genom markprofilen med 20 % och 33 % för respektive scenario. Tidigare skördetidpunkter bidrog också till ökat kväve-läckage på grund av att perioden av obevuxen mark förlängs. Det är viktigt att komma ihåg att denna studie innehåller vissa generaliseringar, och att parameteriseringen representerar en av flera möjliga. Modellexemplet visar dock på ett möjligt tillvägagångsätt för att uppskatta potentiella effekter av klimatförändringen. Fortsatt forskning bör fokusera på växtspecifika egenskaper och parameterisering av grödan, för att undvika resultat som påverkas av för tidig mognad av grödan i ett varmare klimat. Det kan också vara lämpligt att göra så kallade ensemble-simuleringar, där utdata från flera RCM används för att driva en modell för vatten och kväveflöden i mark. 2011-10-18 Second cycle, A1E NonPeerReviewed application/pdf swe https://stud.epsilon.slu.se/3362/1/nanos_t_111018.pdf Nanos, Therése, 2011. Water balance and nitrate leaching from arable land in a changed climate : a model study. Second cycle, A1E. Uppsala: (NL, NJ) > Dept. of Soil and Environment <https://stud.epsilon.slu.se/view/divisions/OID-435.html> urn:nbn:se:slu:epsilon-s-690 eng |
| spellingShingle | Soil science and management Nanos, Therése Water balance and nitrate leaching from arable land in a changed climate |
| title | Water balance and nitrate leaching from arable land in a changed climate |
| title_full | Water balance and nitrate leaching from arable land in a changed climate |
| title_fullStr | Water balance and nitrate leaching from arable land in a changed climate |
| title_full_unstemmed | Water balance and nitrate leaching from arable land in a changed climate |
| title_short | Water balance and nitrate leaching from arable land in a changed climate |
| title_sort | water balance and nitrate leaching from arable land in a changed climate |
| topic | Soil science and management |
| url | https://stud.epsilon.slu.se/3362/ https://stud.epsilon.slu.se/3362/ |