Measuring N uptake and transport in Pinus sylvestris to estimate mycorrhizal transfer efficiency : a tracer/fertilicer experiment in northern Sweden

In a large-scale field experiment, single trees in a Scots pine stand in Northern Sweden were subjected to different amounts of nitrate fertilizer containing the tracer isotope 15N. This was done on two plots, one control plot and one that had been fertilized during the previous 6 seasons, all trees...

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Autor principal: Henriksson, Nils
Formato: H3
Lenguaje:Inglés
Publicado: SLU/Dept. of Forest Ecology and Management 2012
Materias:
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author Henriksson, Nils
author_browse Henriksson, Nils
author_facet Henriksson, Nils
author_sort Henriksson, Nils
collection Epsilon Archive for Student Projects
description In a large-scale field experiment, single trees in a Scots pine stand in Northern Sweden were subjected to different amounts of nitrate fertilizer containing the tracer isotope 15N. This was done on two plots, one control plot and one that had been fertilized during the previous 6 seasons, all trees were about 90 years old. Measurements of needle nitrogen (N) content and delta 15N abundance and analyses of N-forms in the xylem sap were conducted. Also, sap flux density was measured with Granier-type sensors, enabling assessment of when added N may have reached the canopy. The hypotheses were 1) that the ectomycorrhizal N transfer efficiency to the plant partner is enhanced by conditions of high soil N availability; and 2) that N transport through the trees’ xylem is shifted to compounds with lower C/N ratio when the N availability is increased. The results supported the first hypothesis and gave some support to the second. Sap flux measurements indicated a surprisingly slow water transport in the xylem, suggesting that the added N reached the upper canopy four weeks after fertilization. Xylem sap nitrate concentrations exhibited a peak four weeks after fertilizer addition, corroborating the slow xylem transport rates assessed with the Granier elements.
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institution Swedish University of Agricultural Sciences
language Inglés
publishDate 2012
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publisher SLU/Dept. of Forest Ecology and Management
publisherStr SLU/Dept. of Forest Ecology and Management
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spelling RepoSLU42112012-05-23T06:51:17Z Measuring N uptake and transport in Pinus sylvestris to estimate mycorrhizal transfer efficiency : a tracer/fertilicer experiment in northern Sweden Henriksson, Nils Nitrogen xylem sap water transport mycorrhiza transfer efficiency Pinus sylvestris In a large-scale field experiment, single trees in a Scots pine stand in Northern Sweden were subjected to different amounts of nitrate fertilizer containing the tracer isotope 15N. This was done on two plots, one control plot and one that had been fertilized during the previous 6 seasons, all trees were about 90 years old. Measurements of needle nitrogen (N) content and delta 15N abundance and analyses of N-forms in the xylem sap were conducted. Also, sap flux density was measured with Granier-type sensors, enabling assessment of when added N may have reached the canopy. The hypotheses were 1) that the ectomycorrhizal N transfer efficiency to the plant partner is enhanced by conditions of high soil N availability; and 2) that N transport through the trees’ xylem is shifted to compounds with lower C/N ratio when the N availability is increased. The results supported the first hypothesis and gave some support to the second. Sap flux measurements indicated a surprisingly slow water transport in the xylem, suggesting that the added N reached the upper canopy four weeks after fertilization. Xylem sap nitrate concentrations exhibited a peak four weeks after fertilizer addition, corroborating the slow xylem transport rates assessed with the Granier elements. SLU/Dept. of Forest Ecology and Management 2012 H3 eng https://stud.epsilon.slu.se/4211/
spellingShingle Nitrogen
xylem sap
water transport
mycorrhiza
transfer efficiency
Pinus sylvestris
Henriksson, Nils
Measuring N uptake and transport in Pinus sylvestris to estimate mycorrhizal transfer efficiency : a tracer/fertilicer experiment in northern Sweden
title Measuring N uptake and transport in Pinus sylvestris to estimate mycorrhizal transfer efficiency : a tracer/fertilicer experiment in northern Sweden
title_full Measuring N uptake and transport in Pinus sylvestris to estimate mycorrhizal transfer efficiency : a tracer/fertilicer experiment in northern Sweden
title_fullStr Measuring N uptake and transport in Pinus sylvestris to estimate mycorrhizal transfer efficiency : a tracer/fertilicer experiment in northern Sweden
title_full_unstemmed Measuring N uptake and transport in Pinus sylvestris to estimate mycorrhizal transfer efficiency : a tracer/fertilicer experiment in northern Sweden
title_short Measuring N uptake and transport in Pinus sylvestris to estimate mycorrhizal transfer efficiency : a tracer/fertilicer experiment in northern Sweden
title_sort measuring n uptake and transport in pinus sylvestris to estimate mycorrhizal transfer efficiency : a tracer/fertilicer experiment in northern sweden
topic Nitrogen
xylem sap
water transport
mycorrhiza
transfer efficiency
Pinus sylvestris