, Volume 488, Issue 1–3, pp 107–113

Impacts of the C4 sedge Cyperus papyrus L. on carbon and water fluxes in an African wetland



Fluxes of CO2 and H2O vapour were measured by eddy covariance from a stand of the C4 emergent sedge Cyperus papyrus (papyrus), which formed a fringing swamp on the north-west shore of Lake Naivasha, Kenya. The fluxes of CO2 and H2O vapour between the papyrus swamp and the atmosphere were large but variable, depending on the hydrology of the wetland system and the condition of the vegetation. These measurements, combined with simulation modelling of annual fluxes of CO2, show that papyrus swamps have the potential to sequester large amounts of the carbon (∼1.6 kg C m−2 y−1) when detritus accumulates under water in anaerobic conditions, but they are a net source of carbon release to the atmosphere (∼1.0 kg C m−2 y−1) when water levels fall to expose detritus and rhizomes to aerobic conditions. Evapotranspiration from papyrus swamps (E) was frequently lower than evaporation from open water surfaces (Eo) and plant factors have a strong influence on the flux of water to the atmosphere. For the period of measurement E/Eo was 0.36.

Africa Cyperus papyrus L. carbon balance C4 photosynthesis evapotranspiration wetlands 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Anderson, M. G. & S. B. Idso, 1987. Surface geometry and stomatal conductance effects on evaporation from aquatic macrophytes. Wat. Resour. Res. 23: 1037–1042.Google Scholar
  2. Becht, R. & D. M. Harper, 2002. Towards an understanding of human impact upon the hydrology of Lake Naivasha, Kenya. Hydrobiologia 488 (Dev. Hycrobiol. 168): 1–11.Google Scholar
  3. Doliner, L. H. & P. A. Joliffe, 1979. Ecological evidence concerning the adaptive significance of the C4 dicarboxylic acid pathway of photosynthesis. Oecologia 38: 24–34.Google Scholar
  4. Gaudet, J. J., 1977. Natural draw-down on Lake Naivasha, Kenya, and the formation of papyrus swamps. Aquat. Bot. 3: 1–47.Google Scholar
  5. Grace, J. J., J. Llyod, J. Mcintyre, A. Miranda, P. Meir, H. Miranda, J. Moncrieff, J. Massheder, I. Wright & J. Gash, 1995. Fluxes of carbon dioxide and water vapor over an undisturbed tropical forest in south-west Amazon. Global Change Biol. 1: 1–12.Google Scholar
  6. Hasegawa, S., 1977. Agroclimatological studies on C3-plants and C4-plants. Transpiration and leaf temperatures. J. Agric. Meteorol. 33: 129–136.Google Scholar
  7. Hughes, R. H. & J. S. Hughes, 1992. A Directory of African Wetlands. IUCN, Gland, Switzerland and Cambridge, U.K.: 820 pp.Google Scholar
  8. Humphries, S. W. & S. P. Long, 1995. WIMOVAC–a software package for modelling the dynamics of plant leaf and canopy photosynthesis. Computer Applications in the Biosciences 11: 361–371.Google Scholar
  9. Idso, SB., 1981. Relative rates of evaporative water losses from open and vegetation covered water bodies. Wat. Resour. Bull. 17: 46–48.Google Scholar
  10. Idso, S. B. & M. G. Anderson, 1988. A comparison of two recent studies of transpirational water loss from emergent aquatic macrophytes. Aquat. Bot. 31: 191–195.Google Scholar
  11. Jones, M. B., 1987a Wetlands. In Baker N. R. & S. P. Long (eds), Photosynthesis in Contrasting Environments. Elsevier, Amsterdam: 103–138.Google Scholar
  12. Jones, M. B., 1987b. The photosynthetic characteristics of papyrus in a tropical swamp. Oecologia 71: 355–359.Google Scholar
  13. Jones, M. B. & F. M. Muthuri, 1985. The canopy structure and microclimate of papyrus (Cyperus papyrus L. ) swamps. J. Ecol. 73: 481–491.Google Scholar
  14. Jones, M. B. & F. M. Muthuri, 1997. Standing biomass and carbon distribution in a papyrus (Cyperus papyrus L.) swamp on Lake Naivasha, Kenya. J. Trop Ecol. 13: 347–356.Google Scholar
  15. Knapp, A. K. & E. Medina, 1999. Success of C4 photosynthesis in the field: lessons from communities dominated by C4 plants. In Sage R. F. & R. K. Monson (eds), C4 Plant Biology. Academic Press, San Diego: 251–283.Google Scholar
  16. Linacre, E. T., B. B. Hicks, G. R. Sainty & G. Grauze, 1970. The evaporation from a swamp. Agric. Meteorol. 7: 375–386.Google Scholar
  17. Long, S. P., 1999. Environmental responses. In Sage R. F. & R. K. Monson (eds), C4 Plant Biology. Academic Press, San Diego: 215–249.Google Scholar
  18. Moncrieff, J. B., J. M. Massheder, H. DeBruin, J. Elbers, B. Huesunkveld, P. Kabat, S. Scott, H. Soegaard & A. Verhoef, 1997a. A system to measure surface fluxes of momentum, sensible heat, water vapour and carbon dioxide. J. Hydrol. 189: 580–611.Google Scholar
  19. Moncrieff, J., S. Valentini, S. Greco, G. Seufert & P. Ciccioli, 1997b. Trace gas exchange over terrestrial ecosystems: methods and perspectives in micrometeorology. J. exp. Bot. 48: 1133–1142.Google Scholar
  20. Muthuri, F. M., 1985. The Primary Productivity of Papyrus (Cyperus papyrus L.) in Relation to Environmental Variables. PhD Thesis. University of Nairobi, Kenya.Google Scholar
  21. Muthuri, F. M., M. B. Jones & S. K. Imbamba, 1989. Primary productivity of papyrus (Cyperus papyrus L.) in a tropical swamp–Lake Naivasha, Kenya. Biomass 18: 1–14.Google Scholar
  22. O'Toole, J. C. & V. S. Tomar, 1982. Transpiration, leaf temperature and water potential of rice and barnyard grass in flooded fields. Agric. Meteorol. 26: 285–296.Google Scholar
  23. Parkinson, K. J., 1981. An improved method for measuring soil respiration in the field. J. App. Ecol. 18: 221–228.Google Scholar
  24. Penman, H. L., 1948. Natural evaporation from open water, bare soil and grass. Proc. R. Soc. Lond: Series B. 193: 120–145.Google Scholar
  25. Piedade, M. T. F.,W. J. Junk & S. P. Long, 1991. The productivity of the C4 grass Echinochloa polystacha on the Amazon floodplain. Ecology 72: 1456–1463.Google Scholar
  26. Rijks, D. A., 1969. Evaporation from a papyrus swamp. Quart. J. Royal Met. Soc. 95: 643–649.Google Scholar
  27. Schimel, D. S., 1995. Terrestrial ecosystems and the carbon cycle. Global Change Biol. 1: 77–91.Google Scholar
  28. Schuepp, P. H., M. Y. Leclerc, J. I. Macpherson & R. L. Desjardins, 1990. Footprint predictions of scalar fluxes from analytical solutions of the diffusion equation. Boundary Layer Meteorol. 50: 353–373.Google Scholar
  29. Thompson, K. &A. C. Hamilton, 1983. Peatlands and swamps of the African continent. In Gore, A. J. P. (ed.), Ecosystems of the World. Elsevier, Amsterdam: 331–373.Google Scholar

Copyright information

© Kluwer Academic Publishers 2002

Authors and Affiliations

  1. 1.Botany Department, Trinity CollegeUniversity of DublinDublin 2Ireland
  2. 2.Department of Biological SciencesUniversity of EssexColchesterU.K

Personalised recommendations