Hur bra är dagens rekommendationer för markkartering?
For a long time in Sweden, there has been a general practice to perform soil mapping as a basis for manure and lime distribution. The recommendations currently available for how often soil mapping should be performed consist of basic mapping for clay content, organic carbon content, P-AL, K-AL and p...
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| Formato: | Second cycle, A1E |
| Lenguaje: | sueco sueco |
| Publicado: |
2018
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| Acceso en línea: | https://stud.epsilon.slu.se/13176/ |
| _version_ | 1855572200107540480 |
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| author | Ringdahl, Fabian |
| author_browse | Ringdahl, Fabian |
| author_facet | Ringdahl, Fabian |
| author_sort | Ringdahl, Fabian |
| collection | Epsilon Archive for Student Projects |
| description | For a long time in Sweden, there has been a general practice to perform soil mapping as a basis for manure and lime distribution. The recommendations currently available for how often soil mapping should be performed consist of basic mapping for clay content, organic carbon content, P-AL, K-AL and pH. After that a follow-up action is performed approximately every ten years. There is a lack of support for how often a soil mapping needs to be established and according to the literature that has been studied, no studies have been made concerning observed changes of phosphorus content in soil mapping over time. In the present study, eight Swedish farms were included. Soil maps from two different occasions performed on the farms have been compared to evaluate how the amount of AL-extractable phosphorus in soil changed during the period between the soil mappings. Results showed that changes in P content between the occasions could be detected, where an average of about 35 % of the area had an increase in P-AL by more than 20 % and about 14 % of the area had a decrease in P-AL by more than -20 %. However, large differences were found between farms, and on some farms, the phosphorus content had increased in almost the entire area, compared with others were the content had decreased in the majority of the area. Statistical analyses of the changes in P-AL was performed in order to investigate whether it was possible to correlate clay content, organic carbon content, initial P-AL and initial pH with changes of P-AL between the two occasions. It was found that primarily the initial PAL was correlated with the size of the change where lower P-AL values led to a greater positive change and a high P-AL value to major negative changes. For the farms, phosphorus balances were also conducted at field level to compare these with the changes in phosphorus content in the soil maps. Some of the changes can be linked to the fact that phosphorous fertilizer has been spread in order to rise the phosphorus level, but some changes are difficult to explain. One trend shown is that changes are not as expected with respect to the long-term fertility trials, especially when high amounts of phosphorus are applied. Phosphorus balances showed that most farms should have had a general decrease in P-AL values, but that was not the case. Further studies should be done on for how long time high phosphorus applications are able to deliver phosphorus and how close a soil mapping can be established after a high phosphorus application. In order to avoid variations of P-AL values in soil mapping due to high phosphorus applications and in order to see trends of how phosphorus status changes, an alternative would be to change the recommendations so that soil mapping is performed as part of the plant sequence. |
| format | Second cycle, A1E |
| id | RepoSLU13176 |
| institution | Swedish University of Agricultural Sciences |
| language | Swedish swe |
| publishDate | 2018 |
| publishDateSort | 2018 |
| record_format | eprints |
| spelling | RepoSLU131762019-02-26T14:08:40Z https://stud.epsilon.slu.se/13176/ Hur bra är dagens rekommendationer för markkartering? Ringdahl, Fabian Soil surveys and mapping Soil fertility For a long time in Sweden, there has been a general practice to perform soil mapping as a basis for manure and lime distribution. The recommendations currently available for how often soil mapping should be performed consist of basic mapping for clay content, organic carbon content, P-AL, K-AL and pH. After that a follow-up action is performed approximately every ten years. There is a lack of support for how often a soil mapping needs to be established and according to the literature that has been studied, no studies have been made concerning observed changes of phosphorus content in soil mapping over time. In the present study, eight Swedish farms were included. Soil maps from two different occasions performed on the farms have been compared to evaluate how the amount of AL-extractable phosphorus in soil changed during the period between the soil mappings. Results showed that changes in P content between the occasions could be detected, where an average of about 35 % of the area had an increase in P-AL by more than 20 % and about 14 % of the area had a decrease in P-AL by more than -20 %. However, large differences were found between farms, and on some farms, the phosphorus content had increased in almost the entire area, compared with others were the content had decreased in the majority of the area. Statistical analyses of the changes in P-AL was performed in order to investigate whether it was possible to correlate clay content, organic carbon content, initial P-AL and initial pH with changes of P-AL between the two occasions. It was found that primarily the initial PAL was correlated with the size of the change where lower P-AL values led to a greater positive change and a high P-AL value to major negative changes. For the farms, phosphorus balances were also conducted at field level to compare these with the changes in phosphorus content in the soil maps. Some of the changes can be linked to the fact that phosphorous fertilizer has been spread in order to rise the phosphorus level, but some changes are difficult to explain. One trend shown is that changes are not as expected with respect to the long-term fertility trials, especially when high amounts of phosphorus are applied. Phosphorus balances showed that most farms should have had a general decrease in P-AL values, but that was not the case. Further studies should be done on for how long time high phosphorus applications are able to deliver phosphorus and how close a soil mapping can be established after a high phosphorus application. In order to avoid variations of P-AL values in soil mapping due to high phosphorus applications and in order to see trends of how phosphorus status changes, an alternative would be to change the recommendations so that soil mapping is performed as part of the plant sequence. Det har under lång tid i Sverige varit allmän praxis att upprätta en markkartering för att använda som underlag vid beslut om hur insatser i form av gödsel och kalk bör fördelas. De rekommendationer som finns idag för hur ofta en markkartering bör utföras går ut på att en grundkartering upprättas för lerhalt, mullhalt, P-AL, K-AL och pH. Sedan görs en uppföljningskartering med ungefär tio års mellanrum. Det finns dåligt med underlag för hur ofta en markkartering behöver upprättas och enligt den undersökta litteraturen har inga studier gjorts om hur förändringar mellan markkarteringar sett ut. I denna studie inkluderas åtta svenska gårdar. Markkarteringar från två olika tillfällen på gårdarna har jämförts för att undersöka hur fosfortalen förändrades under perioden mellan karteringarna. Förändringar mellan markkarteringarna kunde fastställas, där ett medeltal av ca 35 % av arealen hade ökat med mer än 20 % P-AL-tal och ca 14 % av arealen påvisade en minskning av P-AL-tal med mer än 20 %. Det var stora skillnader mellan gårdarna och på vissa gårdar hade en ökning skett på i stort sett hela arealen medan andra gårdar påvisade en stor minskning på större delen av arealen. Statistiska analyser av förändringarna gjordes för att undersöka om det gick att korrelera lerhalt, mullhalt, ursprungligt P-AL-tal och ursprungligt pH med förändringarna av P-AL. Av de statistiska analyserna framgick att det främst var ursprungligt P-AL som korrelerade med förändringens storlek där lägre P-AL-tal ledde till en större positiv förändring och ett högt P-AL-tal till stora negativa förändringar. För gårdarna togs det även fram fosforbalanser på skiftesnivå för att jämföra dessa med förändringarna av fosfor. En del av förändringarna kan kopplas till att en uppgödsling av fosfor har skett men vissa förändringar är svåra att förklara. Vissa förändringar visade sig inte bli som förväntat med hänseende till de långliggande bördighetsförsöken, särskilt inte där höga givor av fosfor appliceras. Fosforbalanserna visade på att de flesta gårdar borde ha haft en generell minskning av P-AL-talen, men så var inte fallet. En mer omfattande undersökning bör göras om hur länge höga fosforgivor förmår leverera fosfor samt hur nära inpå en applicering av höga fosforgivor som det är lämpligt att upprätta en markkartering. För att komma ifrån variationer av fosfortalen på grund av höga fosforgivor och i sin tur se trender av hur fosforstatusen förändras, skulle ett alternativ vara att ändra rekommendationerna så att markkarteringen utförs som ett led i växtföljden. 2018-03-01 Second cycle, A1E NonPeerReviewed application/pdf sv https://stud.epsilon.slu.se/13176/1/ringdahl_f_180301.pdf Ringdahl, Fabian, 2018. Hur bra är dagens rekommendationer för markkartering? : förändringar av fosforhalter i svensk åkermark över tid. 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-9274 swe |
| spellingShingle | Soil surveys and mapping Soil fertility Ringdahl, Fabian Hur bra är dagens rekommendationer för markkartering? |
| title | Hur bra är dagens rekommendationer för markkartering? |
| title_full | Hur bra är dagens rekommendationer för markkartering? |
| title_fullStr | Hur bra är dagens rekommendationer för markkartering? |
| title_full_unstemmed | Hur bra är dagens rekommendationer för markkartering? |
| title_short | Hur bra är dagens rekommendationer för markkartering? |
| title_sort | hur bra är dagens rekommendationer för markkartering? |
| topic | Soil surveys and mapping Soil fertility |
| url | https://stud.epsilon.slu.se/13176/ https://stud.epsilon.slu.se/13176/ |