Does canopy nitrogen uptake enhance carbon sequestration by trees?

Richard K. F. Nair, Micheal P. Perks, Andrew Weatherall, Elizabeth M. Baggs, Maurizio Mencuccini

Research output: Contribution to journalArticle

7 Citations (Scopus)
11 Downloads (Pure)

Abstract

Temperate forest (15) N isotope trace experiments find nitrogen (N) addition driven carbon (C) uptake is modest as little additional N is acquired by trees, However, several correlations of ambient N deposition against forest productivity imply a greater effect of atmospheric nitrogen deposition than these studies. We asked if N deposition experiments adequately represent all processes found in ambient conditions. In particular, experiments typically apply (15) N to directly to forest floors, assuming uptake of nitrogen intercepted by canopies (CNU) is minimal. Additionally, conventional (15) N additions typically trace mineral (15) N additions rather than litter N recycling and may increase total N inputs above ambient levels. To test the importance of CNU and recycled N to tree nutition, we conducted a mesocosm experiment, applying 54 g N /(15) N ha(-1) y(-1) to Sitka spruce saplings. We compared tree and soil (15) N recovery among treatments where enrichment was due to either 1) a (15) N-enriched litter layer, or mineral (15) N additions to 2) the soil or 3) the canopy. We found that 60 % of (15) N applied to the canopy was recovered above ground (in needles, stem, and branches) while only 21 % of (15) N applied to the soil was found in these pools. (15) N recovery from litter was low and highly variable. (15) N partitioning among biomass pools and age classes and also differed among treatments, with twice as much (15) N found in woody biomass when deposited on the canopy than soil. Stochiometrically calculated N effect on C uptake from (15) N applied to the soil, scaled to real-world conditions, was 43 kg C kg N(-1) , similar to manipulation studies. The effect from the canopy treatment was 114 kg C kg N(-1) . Canopy treatments may be critical to accurately represent N deposition in the field and may address the discrepancy between manipulative and correlative studies.

Original languageEnglish
Pages (from-to)875-888
Number of pages14
JournalGlobal Change Biology
Volume22
Issue number2
Early online date14 Dec 2015
DOIs
Publication statusPublished - Feb 2016

Fingerprint

carbon sequestration
Nitrogen
Carbon
canopy
Soils
nitrogen
litter
soil
Biomass
Experiments
Recovery
experiment
Trace Elements
Isotopes
Needles
biomass allocation
mesocosm
Minerals
mineral
Recycling

Keywords

  • nitrogen deposition
  • Picea sitchensis
  • 15N labelling
  • isotope trace
  • canopy fertilization
  • soil fertilization
  • canopy nitrogen uptake
  • C sequestration

Cite this

Nair, R. K. F., Perks, M. P., Weatherall, A., Baggs, E. M., & Mencuccini, M. (2016). Does canopy nitrogen uptake enhance carbon sequestration by trees? Global Change Biology, 22(2), 875-888. https://doi.org/10.1111/gcb.13096

Does canopy nitrogen uptake enhance carbon sequestration by trees? / Nair, Richard K. F.; Perks, Micheal P.; Weatherall, Andrew; Baggs, Elizabeth M.; Mencuccini, Maurizio.

In: Global Change Biology, Vol. 22, No. 2, 02.2016, p. 875-888.

Research output: Contribution to journalArticle

Nair, RKF, Perks, MP, Weatherall, A, Baggs, EM & Mencuccini, M 2016, 'Does canopy nitrogen uptake enhance carbon sequestration by trees?', Global Change Biology, vol. 22, no. 2, pp. 875-888. https://doi.org/10.1111/gcb.13096
Nair RKF, Perks MP, Weatherall A, Baggs EM, Mencuccini M. Does canopy nitrogen uptake enhance carbon sequestration by trees? Global Change Biology. 2016 Feb;22(2):875-888. https://doi.org/10.1111/gcb.13096
Nair, Richard K. F. ; Perks, Micheal P. ; Weatherall, Andrew ; Baggs, Elizabeth M. ; Mencuccini, Maurizio. / Does canopy nitrogen uptake enhance carbon sequestration by trees?. In: Global Change Biology. 2016 ; Vol. 22, No. 2. pp. 875-888.
@article{4f7be8e04bc64a9ba54340a031456b01,
title = "Does canopy nitrogen uptake enhance carbon sequestration by trees?",
abstract = "Temperate forest (15) N isotope trace experiments find nitrogen (N) addition driven carbon (C) uptake is modest as little additional N is acquired by trees, However, several correlations of ambient N deposition against forest productivity imply a greater effect of atmospheric nitrogen deposition than these studies. We asked if N deposition experiments adequately represent all processes found in ambient conditions. In particular, experiments typically apply (15) N to directly to forest floors, assuming uptake of nitrogen intercepted by canopies (CNU) is minimal. Additionally, conventional (15) N additions typically trace mineral (15) N additions rather than litter N recycling and may increase total N inputs above ambient levels. To test the importance of CNU and recycled N to tree nutition, we conducted a mesocosm experiment, applying 54 g N /(15) N ha(-1) y(-1) to Sitka spruce saplings. We compared tree and soil (15) N recovery among treatments where enrichment was due to either 1) a (15) N-enriched litter layer, or mineral (15) N additions to 2) the soil or 3) the canopy. We found that 60 {\%} of (15) N applied to the canopy was recovered above ground (in needles, stem, and branches) while only 21 {\%} of (15) N applied to the soil was found in these pools. (15) N recovery from litter was low and highly variable. (15) N partitioning among biomass pools and age classes and also differed among treatments, with twice as much (15) N found in woody biomass when deposited on the canopy than soil. Stochiometrically calculated N effect on C uptake from (15) N applied to the soil, scaled to real-world conditions, was 43 kg C kg N(-1) , similar to manipulation studies. The effect from the canopy treatment was 114 kg C kg N(-1) . Canopy treatments may be critical to accurately represent N deposition in the field and may address the discrepancy between manipulative and correlative studies.",
keywords = "nitrogen deposition, Picea sitchensis, 15N labelling, isotope trace, canopy fertilization, soil fertilization, canopy nitrogen uptake, C sequestration",
author = "Nair, {Richard K. F.} and Perks, {Micheal P.} and Andrew Weatherall and Baggs, {Elizabeth M.} and Maurizio Mencuccini",
note = "Acknowledgements We thank Archie Crofton and Radina Atanasova (University of Edinburgh), as well as Colin McEvoy and Carina Convery (Forest Research, UK) for field and technical assistance. We would like to thank Bill Mason (Forest Research UK) for access to the Gisburn Forest tree species trial. Isotope analyses were performed by Nick Morley at the University of Aberdeen, UK. This work was funded by the UK Natural Environment Research Council (NERC), grant NE/G00725 X/1 and Forestry Commission, UK. Funding to pay the open access cost of this publication was provided by NERC.",
year = "2016",
month = "2",
doi = "10.1111/gcb.13096",
language = "English",
volume = "22",
pages = "875--888",
journal = "Global Change Biology",
issn = "1354-1013",
publisher = "John Wiley & Sons, Ltd (10.1111)",
number = "2",

}

TY - JOUR

T1 - Does canopy nitrogen uptake enhance carbon sequestration by trees?

AU - Nair, Richard K. F.

AU - Perks, Micheal P.

AU - Weatherall, Andrew

AU - Baggs, Elizabeth M.

AU - Mencuccini, Maurizio

N1 - Acknowledgements We thank Archie Crofton and Radina Atanasova (University of Edinburgh), as well as Colin McEvoy and Carina Convery (Forest Research, UK) for field and technical assistance. We would like to thank Bill Mason (Forest Research UK) for access to the Gisburn Forest tree species trial. Isotope analyses were performed by Nick Morley at the University of Aberdeen, UK. This work was funded by the UK Natural Environment Research Council (NERC), grant NE/G00725 X/1 and Forestry Commission, UK. Funding to pay the open access cost of this publication was provided by NERC.

PY - 2016/2

Y1 - 2016/2

N2 - Temperate forest (15) N isotope trace experiments find nitrogen (N) addition driven carbon (C) uptake is modest as little additional N is acquired by trees, However, several correlations of ambient N deposition against forest productivity imply a greater effect of atmospheric nitrogen deposition than these studies. We asked if N deposition experiments adequately represent all processes found in ambient conditions. In particular, experiments typically apply (15) N to directly to forest floors, assuming uptake of nitrogen intercepted by canopies (CNU) is minimal. Additionally, conventional (15) N additions typically trace mineral (15) N additions rather than litter N recycling and may increase total N inputs above ambient levels. To test the importance of CNU and recycled N to tree nutition, we conducted a mesocosm experiment, applying 54 g N /(15) N ha(-1) y(-1) to Sitka spruce saplings. We compared tree and soil (15) N recovery among treatments where enrichment was due to either 1) a (15) N-enriched litter layer, or mineral (15) N additions to 2) the soil or 3) the canopy. We found that 60 % of (15) N applied to the canopy was recovered above ground (in needles, stem, and branches) while only 21 % of (15) N applied to the soil was found in these pools. (15) N recovery from litter was low and highly variable. (15) N partitioning among biomass pools and age classes and also differed among treatments, with twice as much (15) N found in woody biomass when deposited on the canopy than soil. Stochiometrically calculated N effect on C uptake from (15) N applied to the soil, scaled to real-world conditions, was 43 kg C kg N(-1) , similar to manipulation studies. The effect from the canopy treatment was 114 kg C kg N(-1) . Canopy treatments may be critical to accurately represent N deposition in the field and may address the discrepancy between manipulative and correlative studies.

AB - Temperate forest (15) N isotope trace experiments find nitrogen (N) addition driven carbon (C) uptake is modest as little additional N is acquired by trees, However, several correlations of ambient N deposition against forest productivity imply a greater effect of atmospheric nitrogen deposition than these studies. We asked if N deposition experiments adequately represent all processes found in ambient conditions. In particular, experiments typically apply (15) N to directly to forest floors, assuming uptake of nitrogen intercepted by canopies (CNU) is minimal. Additionally, conventional (15) N additions typically trace mineral (15) N additions rather than litter N recycling and may increase total N inputs above ambient levels. To test the importance of CNU and recycled N to tree nutition, we conducted a mesocosm experiment, applying 54 g N /(15) N ha(-1) y(-1) to Sitka spruce saplings. We compared tree and soil (15) N recovery among treatments where enrichment was due to either 1) a (15) N-enriched litter layer, or mineral (15) N additions to 2) the soil or 3) the canopy. We found that 60 % of (15) N applied to the canopy was recovered above ground (in needles, stem, and branches) while only 21 % of (15) N applied to the soil was found in these pools. (15) N recovery from litter was low and highly variable. (15) N partitioning among biomass pools and age classes and also differed among treatments, with twice as much (15) N found in woody biomass when deposited on the canopy than soil. Stochiometrically calculated N effect on C uptake from (15) N applied to the soil, scaled to real-world conditions, was 43 kg C kg N(-1) , similar to manipulation studies. The effect from the canopy treatment was 114 kg C kg N(-1) . Canopy treatments may be critical to accurately represent N deposition in the field and may address the discrepancy between manipulative and correlative studies.

KW - nitrogen deposition

KW - Picea sitchensis

KW - 15N labelling

KW - isotope trace

KW - canopy fertilization

KW - soil fertilization

KW - canopy nitrogen uptake

KW - C sequestration

U2 - 10.1111/gcb.13096

DO - 10.1111/gcb.13096

M3 - Article

VL - 22

SP - 875

EP - 888

JO - Global Change Biology

JF - Global Change Biology

SN - 1354-1013

IS - 2

ER -