Ecological Research

, Volume 26, Issue 1, pp 201–208 | Cite as

Plant effects on soil N mineralization are mediated by the composition of multiple soil organic fractions

  • Dario A. FornaraEmail author
  • Richard Bardgett
  • Sibylle Steinbeiss
  • Donald R. Zak
  • Gerd Gleixner
  • David Tilman
Original Article


Despite the topic of soil nitrogen (N) mineralization being well-studied, very few studies have addressed the relative contribution of different plant and soil variables in influencing soil N mineralization rates, and thus the supply of inorganic N to plants. Here, we used data from a well-studied N-limited grassland to address the relative effects of six plant and soil variables on net and on gross rates of soil N mineralization. We also addressed whether plant effects on soil N mineralization were mediated by changes in C and N concentrations of multiple soil organic matter (SOM) fractions. Regression analyses show that key plant traits (i.e., plant C:N ratios and total root mass) were more important than total C and N concentrations of bulk soil in influencing N mineralization. This was mainly because plant traits influenced the C and N concentration (and C:N ratios) of different SOM fractions, which in turn were significantly associated with changes in net and gross N mineralization. In particular, C:N ratios of a labile soil fraction were negatively related to net soil N mineralization rates, whereas total soil C and N concentrations of more recalcitrant fractions were positively related to gross N mineralization. Our study suggests that changes in belowground N-cycling can be better predicted by simultaneously addressing how plant C:N ratios and root mass affect the composition and distribution of different SOM pools in N-limited grassland systems.


Ecosystem process Nitrogen cycling Soil density fractionation Soil organic matter 



We thank Stephen Hart and Dan Binkley, who helped greatly in the interpretation of our results. Saran P. Sohi gave us helpful suggestions on how to perform soil density fractionation analyses. This research was supported by a grant from the University of Minnesota’s Initiative on Renewable Energy and the Environment, by the LTER program of the US National Science Foundation (NSF/DEB-0620652) and a Marie Curie Outgoing Fellowship issued to D.A.F. within the Work Programme 2004, “Structuring the European Research Area” (2002–2006).


  1. Accoe F, Boeckx P, Busschaert J, Hofman G, Van Cleemput O (2004) Gross N transformation rates and net nitrogen mineralization rates related to the C and N contents of soil organic matter fractions in grassland soils of different age. Soil Biol Biochem 36:2075–2087CrossRefGoogle Scholar
  2. Bardgett R (2005) The biology of soil. A community and ecosystem approach. Oxford University Press, OxfordCrossRefGoogle Scholar
  3. Binkley D, Hart S (1989) The components of nitrogen availability assessments in forest soils. Adv Soil Sci 10:57–116Google Scholar
  4. Booth MS, Stark JM, Rastetter E (2005) Controls on nitrogen cycling in terrestrial ecosystems: a synthetic analysis of literature data. Ecol Monogr 75:139–157CrossRefGoogle Scholar
  5. Chapin FS III, Matson P, Mooney H (2002) Principles of terrestrial ecosystem ecology. Springer, New YorkGoogle Scholar
  6. Chung H, Zak DR, Reich P, Ellsworth DS (2007) Plant species richness, elevated CO2, and atmospheric nitrogen deposition alter soil microbial community composition and function. Global Change Biol 13:980–989CrossRefGoogle Scholar
  7. Flessa HW et al (2008) Storage and stability of organic matter and fossil carbon in a Luvisol and Phaeozem with continuous maize cropping: a synthesis. J Plant Nutr Soil Sci 171:36–51CrossRefGoogle Scholar
  8. Fontaine S, Bardoux G, Abbadie L, Mariotti L (2004) Carbon input to soil may decrease soil carbon content. Ecol Lett 7:314–320CrossRefGoogle Scholar
  9. Fornara DA, Tilman D (2008) Plant functional composition influences rates of soil carbon and nitrogen accumulation. J Ecol 96:314–322CrossRefGoogle Scholar
  10. Fornara DA, Tilman D (2009) Ecological mechanisms associated with the positive diversity–productivity relationship in an N-limited grassland. Ecology 90:408–418CrossRefPubMedGoogle Scholar
  11. Fornara DA, Tilman D, Hobbie S (2009) Linkages between plant functional composition, fine root processes and potential net soil nitrogen mineralization rates. J Ecol 97:48–56CrossRefGoogle Scholar
  12. Hart SC, Nason GE, Myrold DD, Perry DA (1994) Dynamics of gross nitrogen transformations in an old-growth forest: the carbon connection. Ecology 75:880–891CrossRefGoogle Scholar
  13. Kuzyakov Y, Friedel JK, Stahr K (2000) Review of mechanisms and quantification of priming effects. Soil Biol Biochem 32:1485–1498CrossRefGoogle Scholar
  14. Lambers JHR, Harpole WS, Tilman D, Knops J, Reich P (2004) Mechanisms responsible for the positive diversity-productivity relationship in Minnesota grasslands. Ecol Lett 7:661–668CrossRefGoogle Scholar
  15. Manzoni S, Jackson RB, Trofymow JA, Porporato A (2008) The global stoichiometry of litter nitrogen mineralization. Science 321:684–686CrossRefPubMedGoogle Scholar
  16. Meier C, Bowman WD (2009) Links between plant litter chemistry, species diversity, and below-ground ecosystem function. Proc Natl Acad Sci USA 105:19780–19785CrossRefGoogle Scholar
  17. Monaghan R, Barraclough D (1997) Contributions to N mineralization from soil macroorganic matter fractions incorporated into two field soils. Soil Biol Biochem 29:1215–1223CrossRefGoogle Scholar
  18. Neff JC, Towsend AR, Gleixner G, Lehman SJ, Turbull J, Bowman WD (2002) Variable effects of nitrogen additions on the stability and turnover of soil carbon. Nature 419:915–917CrossRefPubMedGoogle Scholar
  19. Noguez AM, Escalante AE, Forney LJ, Nava-Mendoza M, Rosas I, Souza V, Garcia-Olíva F (2008) Soil aggregates in a tropical deciduous forest: effects on C and N dynamics, and microbial communities as determined by t-RFLPs. Biogeochemistry 89:209–220CrossRefGoogle Scholar
  20. Parton WJ, Schimel DS, Cole CV, Ojima DS (1987) Analysis of factors controlling soil organic matter levels in Great Plains grasslands. Soil Sci Soc Am J 51:1173–1179CrossRefGoogle Scholar
  21. Schimel JP, Bennett J (2004) Nitrogen mineralization: challenges of a changing paradigm. Ecology 85:591–602CrossRefGoogle Scholar
  22. Schulze WX, Gleixner G, Kaiser K, Guggenberger G, Mann M, Schulze E-D (2005) A proteomic fingerprint of dissolved organic carbon and of soil particles. Oecologia 142:335–343CrossRefPubMedGoogle Scholar
  23. Sohi SP, Mahieu N, Arah JRM, Powlson DS, Madari B, Gaunt JL (2001) A procedure to isolating soil organic matter fractions suitable for modeling. Soil Sci Soc Am J 65:1121–1128CrossRefGoogle Scholar
  24. Sohi SP, Mahieu N, Powlson DS, Madari B, Smittenberg RH, Gaunt JL (2005) Investigating the chemical characteristics of soil organic matter fractions suitable for modeling. Soil Sci Soc Am J 69:1248–1255CrossRefGoogle Scholar
  25. Sollins P, Spycher G, Glassman CA (1984) Net nitrogen mineralization from light- and heavy fraction forest soil organic matter. Soil Biol Biochem 16:31–37CrossRefGoogle Scholar
  26. Sollins P, Homann P, Caldwell BA (1996) Stabilization and destabilization of soil organic matter: mechanisms and controls. Geoderma 74:65–105CrossRefGoogle Scholar
  27. Springob G, Kirchmann H (2003) Bulk soil C to N ratios as a simple measure of net mineralization from stabilized soil organic matter in sandy arable soils. Soil Biol Biochem 35:629–632CrossRefGoogle Scholar
  28. Swanston CW et al (2005) Initial characterization of processes of soil carbon stabilization using forest stand-level radiocarbon enrichment. Geoderma 128:52–62CrossRefGoogle Scholar
  29. Tilman D, Reich PB, Knops J, Wedin D, Mielke T, Lehman C (2001) Diversity and productivity in a long-term grassland experiment. Science 294:843–845CrossRefPubMedGoogle Scholar
  30. Tilman D, Hill J, Lehman C (2006) Carbon-negative biofuels from low-input high-diversity grassland biomass. Science 314:1598–1600CrossRefPubMedGoogle Scholar
  31. Tilman D, Hill J, Lehman C (2007) Response to comment on “carbon-negative biofuels from low-input high-diversity grassland biomass”. Science 316:1567CrossRefGoogle Scholar
  32. Wedin DA, Pastor J (1993) Nitrogen mineralization dynamics in grass monocultures. Oecologia 96:186–192CrossRefGoogle Scholar
  33. Whalen JK, Bottomley PJ, Myrold DD (2000) Carbon and nitrogen mineralization from light- and heavy-fraction additions to soil. Soil Biol Biochem 32:1345–1352CrossRefGoogle Scholar
  34. Zak DR, Holmes WE, White DC, Peacock AD, Tilman D (2003) Plant diversity, soil microbial communities, and ecosystem function: are there any links? Ecology 84:2042–2050CrossRefGoogle Scholar
  35. Zar JH (1999) Biostatistical analysis, 4th edn. Prentice-Hall, Upper Saddle RiverGoogle Scholar
  36. Zhong Z-K, Makeschin F (2006) Comparison of soil nitrogen availability indices under two temperate forest types. Pedosphere 16:273–283CrossRefGoogle Scholar

Copyright information

© The Ecological Society of Japan 2010

Authors and Affiliations

  • Dario A. Fornara
    • 1
    • 2
    Email author
  • Richard Bardgett
    • 2
  • Sibylle Steinbeiss
    • 3
  • Donald R. Zak
    • 4
  • Gerd Gleixner
    • 5
  • David Tilman
    • 6
  1. 1.Environmental Sciences Research InstituteUniversity of UlsterColeraineUK
  2. 2.Soil and Ecosystem Ecology Laboratory, Lancaster Environment CentreLancaster UniversityLancasterUK
  3. 3.Institute of Groundwater EcologyHelmholtz Centre MunichNeuherbergGermany
  4. 4.School of Natural Resources and EnvironmentUniversity of MichiganAnn ArborUSA
  5. 5.Max-Planck-Institute for BiogeochemistryJenaGermany
  6. 6.Department of Ecology, Evolution, and BehaviorUniversity of MinnesotaSt. PaulUSA

Personalised recommendations