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Ecosystems

, Volume 22, Issue 7, pp 1466–1477 | Cite as

Belowground Biomass Response to Nutrient Enrichment Depends on Light Limitation Across Globally Distributed Grasslands

  • Elsa E. ClelandEmail author
  • Eric M. Lind
  • Nicole M. DeCrappeo
  • Elizabeth DeLorenze
  • Rachel Abbott Wilkins
  • Peter B. Adler
  • Jonathan D. Bakker
  • Cynthia S. Brown
  • Kendi F. Davies
  • Ellen Esch
  • Jennifer Firn
  • Scott Gressard
  • Daniel S. Gruner
  • Nicole Hagenah
  • W. Stanley Harpole
  • Yann Hautier
  • Sarah E. Hobbie
  • Kirsten S. Hofmockel
  • Kevin Kirkman
  • Johannes Knops
  • Christopher W. Kopp
  • Kimberly J. La Pierre
  • Andrew MacDougall
  • Rebecca L. McCulley
  • Brett A. Melbourne
  • Joslin L. Moore
  • Suzanne M. Prober
  • Charlotte Riggs
  • Anita C. Risch
  • Martin Schuetz
  • Carly Stevens
  • Peter D. Wragg
  • Justin Wright
  • Elizabeth T. Borer
  • Eric W. Seabloom
Article

Abstract

Anthropogenic activities are increasing nutrient inputs to ecosystems worldwide, with consequences for global carbon and nutrient cycles. Recent meta-analyses show that aboveground primary production is often co-limited by multiple nutrients; however, little is known about how root production responds to changes in nutrient availability. At twenty-nine grassland sites on four continents, we quantified shallow root biomass responses to nitrogen (N), phosphorus (P) and potassium plus micronutrient enrichment and compared below- and aboveground responses. We hypothesized that optimal allocation theory would predict context dependence in root biomass responses to nutrient enrichment, given variation among sites in the resources limiting to plant growth (specifically light versus nutrients). Consistent with the predictions of optimal allocation theory, the proportion of total biomass belowground declined with N or P addition, due to increased biomass aboveground (for N and P) and decreased biomass belowground (N, particularly in sites with low canopy light penetration). Absolute root biomass increased with N addition where light was abundant at the soil surface, but declined in sites where the grassland canopy intercepted a large proportion of incoming light. These results demonstrate that belowground responses to changes in resource supply can differ strongly from aboveground responses, which could significantly modify predictions of future rates of nutrient cycling and carbon sequestration. Our results also highlight how optimal allocation theory developed for individual plants may help predict belowground biomass responses to nutrient enrichment at the ecosystem scale across wide climatic and environmental gradients.

Keywords

belowground biomass fertilization nitrogen Nutrient Network optimal allocation phosphorus roots 

Notes

Acknowledgements

This work was generated using data from the Nutrient Network (http://www.nutnet.org) experiment, funded at the site-scale by individual researchers. Coordination and data management have been supported by funding to E. Borer and E. Seabloom from the National Science Foundation Research Coordination Network (NSF-DEB-1042132) and Long Term Ecological Research (NSF-DEB-1234162 to Cedar Creek LTER) programs, and the Institute on the Environment (DG-0001-13). We also thank the Minnesota Supercomputer Institute for hosting project data and the Institute on the Environment for hosting Network meetings. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the US Government.

Supplementary material

10021_2019_350_MOESM1_ESM.docx (2 mb)
Supplementary material 1 (DOCX 2017 kb)
10021_2019_350_MOESM2_ESM.xlsx (71 kb)
Supplementary material 2 (XLSX 70 kb)

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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Elsa E. Cleland
    • 1
    Email author
  • Eric M. Lind
    • 2
  • Nicole M. DeCrappeo
    • 3
  • Elizabeth DeLorenze
    • 3
  • Rachel Abbott Wilkins
    • 4
  • Peter B. Adler
    • 5
  • Jonathan D. Bakker
    • 6
  • Cynthia S. Brown
    • 7
  • Kendi F. Davies
    • 8
  • Ellen Esch
    • 9
  • Jennifer Firn
    • 10
  • Scott Gressard
    • 1
  • Daniel S. Gruner
    • 11
  • Nicole Hagenah
    • 12
  • W. Stanley Harpole
    • 13
    • 14
    • 15
  • Yann Hautier
    • 16
  • Sarah E. Hobbie
    • 2
  • Kirsten S. Hofmockel
    • 17
    • 18
  • Kevin Kirkman
    • 19
  • Johannes Knops
    • 20
  • Christopher W. Kopp
    • 21
  • Kimberly J. La Pierre
    • 22
  • Andrew MacDougall
    • 9
  • Rebecca L. McCulley
    • 23
  • Brett A. Melbourne
    • 8
  • Joslin L. Moore
    • 24
  • Suzanne M. Prober
    • 25
  • Charlotte Riggs
    • 2
  • Anita C. Risch
    • 26
  • Martin Schuetz
    • 26
  • Carly Stevens
    • 27
  • Peter D. Wragg
    • 28
  • Justin Wright
    • 29
  • Elizabeth T. Borer
    • 2
  • Eric W. Seabloom
    • 2
  1. 1.Ecology, Behavior and Evolution SectionUniversity of California San DiegoLa JollaUSA
  2. 2.Department of Ecology, Evolution, and BehaviorUniversity of MinnesotaSt. PaulUSA
  3. 3.U.S. Geological Survey, Forest and Rangeland Ecosystem Science CenterCorvallisUSA
  4. 4.Department of Ecology and Evolutionary BiologyCornell UniversityIthacaUSA
  5. 5.Department of Wildland Resources and the Ecology CenterUtah State UniversityLoganUSA
  6. 6.School of Environmental and Forest SciencesUniversity of WashingtonSeattleUSA
  7. 7.Department of Bioagricultural Sciences and Pest Management, Graduate Degree Program in Ecology, 1177 Campus DeliveryColorado State UniversityFort CollinsUSA
  8. 8.Department of Ecology and Evolutionary BiologyUCB 334 University of ColoradoBoulderUSA
  9. 9.Department of Integrative BiologyUniversity of GuelphGuelphCanada
  10. 10.School of Earth, Environmental and Biological SciencesQueensland University of TechnologyBrisbaneAustralia
  11. 11.Department of EntomologyUniversity of MarylandCollege ParkUSA
  12. 12.Department of Zoology and Entomology, Mammal Research InstituteUniversity of PretoriaPretoriaSouth Africa
  13. 13.Department of Physiological DiversityHelmholtz Center for Environmental Research - UFZLeipzigGermany
  14. 14.German Centre for Integrative Biodiversity Research iDiv. Halle-Jena-LeipzigLeipzigGermany
  15. 15.Institute of BiologyMartin Luther University Halle- WittenbergHalle (Saale)Germany
  16. 16.Ecology and Biodiversity Group, Department of BiologyUtrecht UniversityUtrechtThe Netherlands
  17. 17.Department of Ecology, Evolution and Organismal BiologyIowa State UniversityAmesUSA
  18. 18.Environmental Molecular Sciences LaboratoryPacific Northwest National LaboratoryRichlandUSA
  19. 19.School of Life SciencesUniversity of KwaZulu-NatalScottsvilleSouth Africa
  20. 20.School of Biological SciencesUniversity of NebraskaLincolnUSA
  21. 21.Department of BotanyUniversity of British ColumbiaVancouverCanada
  22. 22.Smithsonian Environmental Research CenterEdgewaterUSA
  23. 23.Department of Plant and Soil SciencesUniversity of KentuckyLexingtonUSA
  24. 24.School of Biological SciencesMonash UniversityVictoriaAustralia
  25. 25.CSIRO Land and WaterFloreatAustralia
  26. 26.Swiss Federal Institute for Forest, Snow and Landscape ResearchBirmensdorfSwitzerland
  27. 27.Lancaster Environment CenterLancaster UniversityLancasterUK
  28. 28.Department of Forest ResourcesUniversity of MinnesotaSaint PaulUSA
  29. 29.Department of BiologyDuke UniversityDurhamUSA

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