, Volume 164, Issue 2, pp 511–520 | Cite as

Litter evenness influences short-term peatland decomposition processes

  • Susan E. Ward
  • Nick J. Ostle
  • Niall P. McNamara
  • Richard D. Bardgett
Ecosystem ecology - Original Paper


There is concern that changes in climate and land use could increase rates of decomposition in peatlands, leading to release of stored C to the atmosphere. Rates of decomposition are driven by abiotic factors such as temperature and moisture, but also by biotic factors such as changes in litter quality resulting from vegetation change. While effects of litter species identity and diversity on decomposition processes are well studied, the impact of changes in relative abundance (evenness) of species has received less attention. In this study we investigated effects of changes in short-term peatland plant species evenness on decomposition in mixed litter assemblages, measured as litter weight loss, respired CO2 and leachate C and N. We found that over the 307-day incubation period, higher levels of species evenness increased rates of decomposition in mixed litters, measured as weight loss and leachate dissolved organic N. We also found that the identity of the dominant species influenced rates of decomposition, measured as weight loss, CO2 flux and leachate N. Greatest rates of decomposition were when the dwarf shrub Calluna vulgaris dominated litter mixtures, and lowest rates when the bryophyte Pleurozium schreberi dominated. Interactions between evenness and dominant species identity were also detected for litter weight loss and leachate N. In addition, positive non-additive effects of mixing litter were observed for litter weight loss. Our findings highlight the importance of changes in the evenness of plant community composition for short-term decomposition processes in UK peatlands.


Functional traits Carbon dioxide Leachate Calluna vulgaris Bryophytes 



We are grateful to Jan Poskitt and Susie Fawley for assistance in the laboratory, and to Natural England for allowing us to use the field site. We also thank two anonymous referees and the Editor for helpful comments on an earlier version of this manuscript. This study was supported by a Natural Environment Research Council studentship.


  1. Aerts R, Verhoeven JTA, Whigham DF (1999) Plant-mediated controls on nutrient cycling in temperate fens and bogs. Ecology 80:2170–2181CrossRefGoogle Scholar
  2. Anderson JM, Ineson P (1982) A soil microcosm system and its application to measurements of respiration and nutrient leaching. Soil Biol Biochem 14:415–416CrossRefGoogle Scholar
  3. Ayres E, Steltzer H, Berg S, Wall DH (2009) Soil biota accelerate decomposition in high-elevation forests by specializing in the breakdown of litter produced by the plant species above them. J Ecol 97:901–912CrossRefGoogle Scholar
  4. Ball BA, Hunter MD, Kominoski JS, Swan CM, Bradford MA (2008) Consequences of non-random species loss for decomposition dynamics: experimental evidence for additive and non-additive effects. J Ecol 96:303–313CrossRefGoogle Scholar
  5. Bardgett RD (2005) The biology of soil. A community and ecosystem approach. Oxford University Press, OxfordGoogle Scholar
  6. Bardgett RD, Shine A (1999) Linkages between plant litter diversity, soil microbial biomass and ecosystem function in temperate grasslands. Soil Biol Biochem 31:317–321CrossRefGoogle Scholar
  7. Bardgett RD, Marsden JH, Howard DC (1995) The extent and condition of heather on moorland in the uplands of England and Wales. Biol Conserv 71:155–161CrossRefGoogle Scholar
  8. Bardgett RD, Streeter TC, Bol R (2003) Soil microbes compete effectively with plants for organic-nitrogen inputs to temperate grasslands. Ecology 84:1277–1287CrossRefGoogle Scholar
  9. Begon M, Harper JL, Townsend CR (1996) Ecology. Blackwell Science, OxfordGoogle Scholar
  10. Blair JM, Parmelee RW, Beare MH (1990) Decay-rates, nitrogen fluxes, and decomposer communities of single-species and mixed-species foliar litter. Ecology 71:1976–1985CrossRefGoogle Scholar
  11. Bubier J, Crill P, Mosedale A, Frolking S, Linder E (2003) Peatland responses to varying interannual moisture conditions as measured by automatic CO2 chambers. Glob Biogeochem Cycles 17(2):1066. doi: 10.1029/2002GB001946 CrossRefGoogle Scholar
  12. Cornelissen JHC, van Bodegom PM, Aerts R, Callaghan TV, van Logtestijn RSP, Alatalo J, Chapin FS, Gerdol R, Gudmundsson J, Gwynn-Jones D, Hartley AE, Hik DS, Hofgaard A, Jonsdottir IS, Karlsson S, Klein JA, Laundre J, Magnusson B, Michelsen A, Molau U, Onipchenko VG, Quested HM, Sandvik SM, Schmidt IK, Shaver GR, Solheim B, Soudzilovskaia NA, Stenstrom A, Tolvanen A, Totland O, Wada N, Welker JM, Zhao XQ (2007a) Global negative vegetation feedback to climate warming responses of leaf litter decomposition rates in cold biomes. Ecol Lett 10:619–627CrossRefPubMedGoogle Scholar
  13. Cornelissen JHC, Lang SI, Soudzilovskaia NA, During HJ (2007b) Comparative cryptogam ecology: a review of bryophyte and lichen traits that drive biogeochemistry. Ann Bot 99:987–1001CrossRefPubMedGoogle Scholar
  14. Cornwell WK, Cornelissen JHC, Amatangelo K, Dorrepaal E, Eviner VT, Godoy O, Hobbie SE, Hoorens B, Kurokawa H, Perez-Harguindeguy N, Quested HM, Santiago LS, Wardle DA, Wright IJ, Aerts R Allison SD, van Bodegom P, Brovkin V, Chatain A, Callaghan TV, Diaz S, Garnier E, Gurvich DE, Kazakou E, Klein JA, Read J, Reich PB, Soudzilovskaia NA, Vaierett MV, Westoby M (2008) Plant species traits are the predominant control on litter decomposition rates within biomes worldwide. Ecol Lett 11:1065–1071CrossRefPubMedGoogle Scholar
  15. De Deyn GB, Cornelissen JHC, Bardgett RD (2008) Plant functional traits and soil carbon sequestration in contrasting biomes. Ecol Lett 11:516–531CrossRefPubMedGoogle Scholar
  16. DeLuca TH, Nilsson MC, Zachrisson O (2002) Quantifying nitrogen-fixation in feather moss carpets of boreal forests. Nature 419:917–920CrossRefPubMedGoogle Scholar
  17. Dickson TL, Wilsey BJ (2009) Biodiversity and tallgrass prairie decomposition: the relative importance of species identity, evenness, richness and micro-topography. Plant Ecol 201:639–649CrossRefGoogle Scholar
  18. Dorrepaal E, Toet S, van Logtestijn RSP, Swart E, van de Weg MJ, Callaghan TV, Aerts R (2009) Carbon respiration from subsurface peat accelerated by climate warming in the subarctic. Nature 460:616–620CrossRefGoogle Scholar
  19. Freeman C, Fenner N, Ostle NJ, Kang H, Dowrick DJ, Reynolds B, Lock MA, Sleep D, Hughes S, Hudson J (2004) Export of dissolved organic carbon from peatlands under elevated carbon dioxide levels. Nature 430:195–198CrossRefPubMedGoogle Scholar
  20. Golovatskaya EA, Dyukarev EA (2009) Carbon budget of oligotrophic mire sites in the Southern Taiga of Western Siberia. Plant Soil 315:19–34CrossRefGoogle Scholar
  21. Gorham E (1991) Northern peatlands: role in the carbon cycle and probable responses to climatic warming. Ecol Appl 1:182–195CrossRefGoogle Scholar
  22. Hättenschwiler S, Tiunov AV, Scheu S (2005) Biodiversity and litter decomposition in terrestrial ecosystems. Annu Rev Ecol Syst 36:191–218CrossRefGoogle Scholar
  23. Hector A, Beale AJ, Minns A, Otway SJ, Lawton JH (2000) Consequences of the reduction of plant diversity for litter decomposition: effects through litter quality and microenvironment. Oikos 90:357–371CrossRefGoogle Scholar
  24. Heikkinen JEP, Maljanen M, Aurela M, Hargreaves KJ, Martikainen PJ (2002) Carbon dioxide and methane dynamics in a sub-Arctic peatland in northern Finland. Polar Res 21:49–62CrossRefGoogle Scholar
  25. Hillebrand H, Bennett DM, Cadotte MW (2008) Consequences of dominance: a review of evenness effects on local and regional ecosystem processes. Ecology 89:1510–1520Google Scholar
  26. Hobbie SE (1992) Effects of plant-species on nutrient cycling. Trends Ecol Evol 7:336–339CrossRefGoogle Scholar
  27. Hobbie SE (1996) Temperature and plant species control over litter decomposition in Alaskan tundra. Ecol Monogr 66:503–522CrossRefGoogle Scholar
  28. Holland EA, Robertson GP, Greenberg J, Groffman PM, Boone RD, Gosz JR (1999) Soil CO2, N2O, and CH4 exchange. In: Robertson GP, Coleman DC, Bledsoe CS, Sollins P (eds) Standard soil methods for long-term ecological research. Oxford University Press, Oxford, pp 185–201Google Scholar
  29. Huston MA (1994) Biological diversity. The coexistance of species on changing landscapes. Cambridge University Press, UKGoogle Scholar
  30. Immirzi CP, Maltby E, Clymo RS (1992) The global status of peatlands and their role in carbon cycling. A report for Friends of the Earth by the Wetland Ecosystems Research Group. Friends of the Earth Trust, LondonGoogle Scholar
  31. Johnson LC, Shaver GR, Cades DH, Rastetter E, Nadelhoffer K, Giblin A, Laundre J, Stanley A (2000) Plant carbon-nutrient interactions control CO2 exchange in Alaskan wet sedge tundra ecosystems. Ecology 81:453–469Google Scholar
  32. Jonsson M, Wardle DA (2008) Context dependency of litter-mixing effects on decomposition and nutrient release across a long-term chronosequence. Oikos 117:1674–1682CrossRefGoogle Scholar
  33. King RF, Dromph KM, Bardgett RD (2002) Changes in species evenness of litter have no effect on decomposition processes. Soil Biol Biochem 34:1959–1963CrossRefGoogle Scholar
  34. Kirwan L, Luescher A, Sebastia MT, Finn JA, Collins RP, Porqueddu C, Helgadottir A, Baadshaug OH, Brophy C, Coran C, Dalmannsdottir S, Delgado I, Elgersma A, Fothergill M, Frankow-Lindberg BE, Golinski P, Grieu P, Gustavsson AM, Hoglind M, Huguenin-Elie O, Iliadis C, Jorgensen M, Kadziuliene Z, Karyotis T, Lunnan T, Malengier M, Maltoni S, Meyer V, Nyfeler D, Nykanen-Kurki P, Parente J, Smit HJ, Thumm U, Connolly J (2007) Evenness drives consistent diversity effects in intensive grassland systems across 28 European sites. J Ecol 95:530–539CrossRefGoogle Scholar
  35. Lang SI, Cornelissen JHC, Klahn T, van Logtestijn RSP, Broekman R, Schweikert W, Aerts R (2009) An experimental comparison of chemical traits and litter decomposition rates in a diverse range of subarctic bryophyte, lichen and vascular plant species. J Ecol 97:886–900CrossRefGoogle Scholar
  36. Latter PM, Howson G, Howard DM, Scott WA (1998) Long-term study of litter decomposition on a Pennine peat bog: which regression? Oecologia 113:94–103CrossRefGoogle Scholar
  37. Limpens J, Berendse F (2003) How litter quality affects mass loss and N loss from decomposing Sphagnum. Oikos 103:537–547CrossRefGoogle Scholar
  38. Mattingly WB, Hewlate R, Reynolds HL (2007) Species evenness and invasion resistance of experimental grassland communities. Oikos 116:1164–1170CrossRefGoogle Scholar
  39. McNamara NP, Plant T, Oakley S, Ward S, Wood C, Ostle N (2008) Gully hotspot contribution to landscape methane (CH4) and carbon dioxide (CO2) fluxes in a northern peatland. Sci Total Environ 404:354–360CrossRefPubMedGoogle Scholar
  40. McTiernan KB, Ineson P, Coward PA (1997) Respiration and nutrient release from tree leaf litter mixtures. Oikos 78:527–538CrossRefGoogle Scholar
  41. Moore TR, Bubier JL, Frolking SE, Lafleur PM, Roulet NT (2002) Plant biomass and production and CO2 exchange in an ombotrophic bog. J Ecol 67:789–807Google Scholar
  42. Moore TR, Trofymow JA, Siltanen M, Kozak LM (2008) Litter decomposition and nitrogen and phosphorus dynamics in peatlands and uplands over 12 years in central Canada. Oecologia 157:317–325CrossRefPubMedGoogle Scholar
  43. Mulder CPH, Bazeley-White E, Dimitrakopoulos PG, Hector A, Scherer-Lorenzen M, Schmid B (2004) Species evenness and productivity in experimental plant communities. Oikos 107:50–63CrossRefGoogle Scholar
  44. Prescott CE (2005) Do rates of litter decomposition tell us anything we really need to know? For Ecol Manage 220:66–74CrossRefGoogle Scholar
  45. Rawes M, Heal OW (1978) The blanket bog as part of a Pennine moorland. In: Heal OW, Perkins DF (eds) Production ecology of British moors and montane grasslands. Springer, Berlin, pp 224–243Google Scholar
  46. Rodwell JS (1991) British plant communities. Mires and heaths, vol 2. Cambridge University Press, CambridgeGoogle Scholar
  47. Ross DJ (1992) Influence of sieve mesh size on estimates of microbial carbon and nitrogen by fumigation-extraction procedures in soils under pasture. Soil Biol Biochem 24:343–350CrossRefGoogle Scholar
  48. Roulet NT, Lafleurs PM, Richard PJH, Moore TR, Humphreys ER, Bubier J (2007) Contemporary carbon balance and late Holocene carbon accumulation in a northern peatland. Glob Change Biol 13:397–411CrossRefGoogle Scholar
  49. Schimel JP, Bennett J (2004) Nitrogen mineralization: challenges of a changing paradigm. Ecology 85(3):591–602CrossRefGoogle Scholar
  50. Smith VC, Bradford MA (2003) Do non-additive effects on decomposition in litter-mix experiments result from differences in resource quality between litters? Oikos 102:235–242CrossRefGoogle Scholar
  51. Swan CM, Gluth MA, Horne CL (2009) Leaf litter species evenness influences nonadditive breakdown in a headwater stream. Ecology 90(6):1650–1658CrossRefPubMedGoogle Scholar
  52. Trinder CJ, Artz RRE, Johnson D (2008) Contribution of plant photosynthate to soil respiration and dissolved organic carbon in a naturally recolonising cutover peatland. Soil Biol Biochem 40:1622–1628CrossRefGoogle Scholar
  53. Ward SE, Bardgett RD, McNamara NP, Adamson JK, Ostle NJ (2007) Long-term consequences of grazing and burning on northern peatland carbon dynamics. Ecosystems 10:1069–1083CrossRefGoogle Scholar
  54. Ward SE, Bardgett RD, McNamara NP, Ostle NJ (2009) Plant functional group identity influences short-term peatland ecosystem flux: evidence from a plant removal experiment. Funct Ecol 23:454–462CrossRefGoogle Scholar
  55. Wardle DA, Bonner KI, Nicholson KS (1997) Biodiversity and plant litter: experimental evidence which does not support the view that enhanced species richness improves ecosystem function. Oikos 79:247–258CrossRefGoogle Scholar
  56. Wardle DA, Nilsson MC, Zackrisson O, Gallet C (2003) Determinants of litter mixing effects in a Swedish boreal forest. Soil Biol Biochem 35:827–835CrossRefGoogle Scholar
  57. Wilsey BJ, Potvin C (2000) Biodiversity and ecosystem functioning: importance of species evenness in an old field. Ecology 81:887–892CrossRefGoogle Scholar
  58. Wilsey BJ, Chalcraft DR, Bowles CM, Willig MR (2005) Relationships among indices suggest that richness is an incomplete surrogate for grassland biodiversity. Ecology 86:1178–1184CrossRefGoogle Scholar
  59. Zimmer M (2002) Is decomposition of woodland leaf litter influenced by its species richness? Soil Biol Biochem 34:277–284CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Susan E. Ward
    • 1
    • 2
  • Nick J. Ostle
    • 2
  • Niall P. McNamara
    • 2
  • Richard D. Bardgett
    • 1
  1. 1.Soil and Ecosystem Ecology Laboratory, Lancaster Environment CentreLancaster UniversityLancasterUK
  2. 2.Centre for Ecology and HydrologyLancaster Environment CentreLancasterUK

Personalised recommendations