Oecologia

, Volume 147, Issue 1, pp 47–52

Hemiparasite abundance in an alpine treeline ecotone increases in response to atmospheric CO2 enrichment

Population Ecology

Abstract

Populations of the annual hemiparasites Melampyrum pratense L. and Melampyrum sylvaticum L. were studied at the treeline in the Swiss Alps after 3 years of in situ CO2 enrichment. The total density of Melampyrum doubled to an average of 44 individuals per square meter at elevated CO2 compared to ambient CO2. In response to elevated CO2, the height of the more abundant and more evenly distributed M. pratense increased by 20%, the number of seeds per fruit by 21%, and the total seed dry mass per fruit by 27%, but the individual seed size did not change. These results suggest that rising atmospheric CO2 may stimulate the reproductive output and increase the abundance of Melampyrum in the alpine treeline ecotone. Because hemiparasites can have important effects on community dynamics and ecosystem processes, notably the N cycle, changing Melampyrum abundance may potentially influence the functioning of alpine ecosystems in a future CO2-rich atmosphere.

Keywords

Elevated CO2 Melampyrum pratense Reproduction Plant growth Swiss Alps 

References

  1. Asshoff R, Hättenschwiler S (2005) Growth and reproduction of the alpine grasshopper Miramella alpina feeding on CO2-enriched dwarf shrubs at treeline. Oecologia 142:191–201PubMedCrossRefGoogle Scholar
  2. Berendse F, Schmidt M, De Visser W (1994) Experimental manipulation of succession in heathland ecosystems. Oecologia 100:38–44CrossRefGoogle Scholar
  3. Bret-Harte MS, Garcia EA, Sacre VM, Whorley JR, Wagner JL, Lippert SC, Chapin FS III (2004) Plant and soil responses to neighbour removal and fertilization in Alaskan tussock tundra. J Ecol 92:635–647CrossRefGoogle Scholar
  4. Callaway RM, Pennings SC (1998) Impact of a parasitic plant on the zonation of two salt marsh perennials. Oecologia 114:100–105CrossRefGoogle Scholar
  5. Davies DM, Graves JD, Elias CO, Williams PJ (1997) The impact of Rhinanthus spp. on sward productivity and composition: implications for the restoration of species-rich grasslands. Biol Conserv 78:87–93CrossRefGoogle Scholar
  6. Fischer M, Matthies D, Schmid B (1997) Responses of rare calcareous grassland plants to elevated CO2: a field experiment with Gentianella germanica and Gentiana cruciata. J Ecol 85:681–691CrossRefGoogle Scholar
  7. Gibson CC, Watkinson AR (1991) Host selectivity and the mediation of competition by the root hemiparasite Rhinanthus minor. Oecologia 86:81–87CrossRefGoogle Scholar
  8. Grünzweig JM, Körner C (2001) Biodiversity effects of elevated CO2 in species-rich model communities from the semi-arid Negev of Israel. Oikos 95:112–124CrossRefGoogle Scholar
  9. Hättenschwiler S, Körner C (1996) System-level adjustments to elevated CO2 in model spruce ecosystems. Global Change Biol 2:377–387CrossRefGoogle Scholar
  10. Hättenschwiler S, Körner C (1997) Growth of autotrophic and root-hemiparasitic understorey plants under elevated CO2 and increased N deposition. Acta Oecol 18:327–333CrossRefGoogle Scholar
  11. Hättenschwiler S, Handa IT, Egli L, Asshoff R, Ammann W, Körner C (2002) Atmospheric CO2 enrichment of alpine treeline conifers. New Phytol 156:363–375CrossRefGoogle Scholar
  12. Hungate BA, Holland EA, Jackson RB, Chapin FS III, Mooney HA, Field CB (1997) The fate of carbon in grasslands under carbon dioxide enrichment. Nature 388:576–579CrossRefGoogle Scholar
  13. Jackson RB, Sala OE, Field CB (1994) CO2 alters water use, carbon gain, and yield for the dominant species in a natural grassland. Oecologia 98:257–262CrossRefGoogle Scholar
  14. Joshi J, Matthies D, Schmid B (2000) Root hemiparasites and plant diversity in experimental grassland communities. J Ecol 88:634–644CrossRefGoogle Scholar
  15. Körner C (2000) Biosphere responses to CO2 enrichment. Ecol Appl 10:1590–1619Google Scholar
  16. Körner C (2003) Ecological impacts of atmospheric CO2 enrichment on terrestrial ecosystems. Philos Trans R Soc Lond A 361:2023–2041CrossRefGoogle Scholar
  17. Marvier MA (1998) Parasite impacts on host communities: plant parasitism in a Californian coastal prairie. Ecology 79:2616–2623Google Scholar
  18. Matthies D (1996) Interactions between the root hemiparasite Melampyrum arvense and mixtures of host plants: heterotrophic benefit and parasite-mediated competition. Oikos 75:118–124CrossRefGoogle Scholar
  19. Matthies D (1997) Parasite–host interactions in Castilleja and Orthocarpus. Can J Bot 75:1252–1260CrossRefGoogle Scholar
  20. Matthies D, Egli P (1999) Responses of a root hemiparasite to elevated CO2 depends on host type and soil nutrients. Oecologia 120:156–161CrossRefGoogle Scholar
  21. Phoenix GK, Press MC (2005) Linking physiological traits to impacts on community structure and function: the role of root hemiparasitic Orobanchaceae (ex-Scrophulariaceae). J Ecol 93:67–78CrossRefGoogle Scholar
  22. Press MC (1989) Autotrophy and heterotrophy in root hemiparasites. Trends Ecol Evol 4:258–263CrossRefGoogle Scholar
  23. Press MC (1998) Dracula or Robin Hood? A functional role for root hemiparasites in nutrient poor ecosystems. Oikos 82:609–611CrossRefGoogle Scholar
  24. Press MC, Shah N, Touhy JM, Stewart GR (1987) Carbon isotope ratios demonstrate carbon flux from C4 host to C3 parasite. Plant Physiol 84:814–819PubMedCrossRefGoogle Scholar
  25. Press MC, Smith S, Stewart GR (1991) Carbon acquisition and assimilation in parasitic plants. Funct Ecol 5:278–283CrossRefGoogle Scholar
  26. Quested HM, Cornelissen JH, Press MC, Callaghan TV, Aerts R, Trosien F, Riemann P, Gwynn-Jones D, Kondratchuk A, Jonasson SE (2003a) Decomposition of sub-arctic plants with differing nitrogen economies: a functional role for hemiparasites. Ecology 84:3209–3221CrossRefGoogle Scholar
  27. Quested HM, Press MC, Callaghan TV (2003b) Litter of the hemiparasite Bartsia alpina enhances plant growth: evidence for a functional role in nutrient cycling. Oecologia 135:606–614PubMedGoogle Scholar
  28. Schäppi B (1996) Growth dynamics and population development in an alpine grassland under elevated CO2. Oecologia 106:93–99Google Scholar
  29. Schönenberger W, Frey W (1988) Untersuchungen zur Ökologie und Technik der Hochlagenaufforstung. Forschungsergebnisse aus dem Lawinenanrissgebiet Stillberg. Schweiz Zeitschr Forstw 139:735–820Google Scholar
  30. Smith SD, Huxman TE, Zitzer SF, Charlet TN, Housman DC, Coleman JS, Fenstermaker LK, Seeman JR, Novak RS (2000) Elevated CO2 increases productivity and invasive species success in an arid ecosystem. Nature 408:79–82CrossRefPubMedGoogle Scholar
  31. Tennakoon KU, Pate JS (1996) Heterotrophic gain of carbon from hosts by the xylem-tapping root hemiparasite Olax phyllanthi (Olacaceae). Oecologia 105:369–376CrossRefGoogle Scholar
  32. Thürig B, Körner C, Stöcklin J (2003) Seed production and seed quality in a calcareous grassland in elevated CO2. Global Change Biol 9:873–884CrossRefGoogle Scholar
  33. Westbury DB, Dunnett NP (2000) The effect of the presence of Rhinanthus minor on the composition and productivity of created swards on ex-arable land. Aspects Appl Biol 58:271–278Google Scholar

Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  1. 1.Centre d’Ecologie Fonctionnelle et EvolutiveCEFE-CNRSMontpellier Cedex 5France
  2. 2.Botanisches InstitutUniversität BaselBaselSwitzerland

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