Advertisement

Oecologia

, Volume 135, Issue 4, pp 639–647 | Cite as

Daphnia versus copepod impact on summer phytoplankton: functional compensation at both trophic levels

  • Ulrich Sommer
  • Frank Sommer
  • Barbara Santer
  • Eckart Zöllner
  • Klaus Jürgens
  • Colleen Jamieson
  • Maarten Boersma
  • Klaus Gocke
Community Ecology

Abstract

Here we report on a mesocom study performed to compare the top-down impact of microphagous and macrophagous zooplankton on phytoplankton. We exposed a species-rich, summer phytoplankton assemblage from the mesotrophic Lake Schöhsee (Germany) to logarithmically scaled abundance gradients of the microphagous cladoceran Daphnia hyalina×galeata and of a macrophagous copepod assemblage. Total phytoplankton biomass, chlorophyll a and primary production showed only a weak or even insignificant response to zooplankton density in both gradients. In contrast to the weak responses of bulk parameters, both zooplankton groups exerted a strong and contrasting influence on the phytoplankton species composition. The copepods suppressed large phytoplankton, while nanoplanktonic algae increased with increasing copepod density. Daphnia suppressed small algae, while larger species compensated in terms of biomass for the losses. Autotrophic picoplankton declined with zooplankton density in both gradients. Gelatinous, colonial algae were fostered by both zooplankton functional groups, while medium-sized (ca. 3,000 µm3), non-gelatinous algae were suppressed by both. The impact of a functionally mixed zooplankton assemblage became evident when Daphnia began to invade and grow in copepod mesocosms after ca. 10 days. Contrary to the impact of a single functional group, the combined impact of both zooplankton groups led to a substantial decline in total phytoplankton biomass.

Keywords

Phytopankton Zooplankton Copepoda Cladocera Top-down-control 

Notes

Acknowledgements

The experiments were sponsored by the Deutsche Forschungsgemeinschaft. Technical support by the staff of the Institut für Meereskunde at Kiel and the Max-Planck-Institute of Limnology at Plön is gratefully acknowledged.

References

  1. Abrams PA (1993) Effect of increased productivity on the abundance of trophic levels. Am Nat 141:351–371CrossRefGoogle Scholar
  2. Adrian R, Schneider-Olt B (1999) Top-down effects of crustacean zooplankton on pelagic microorganisms in a mesotrophic lake. J Plankton Res 21:2175–2190CrossRefGoogle Scholar
  3. Bautista B, Harris RP, Tranter PRG, Harbour D (1992) In situ copepod feeding and grazing rates during a spring bloom dominated by Phaeocystis sp. in the English Channel. J Plankton Res 14:691–703Google Scholar
  4. Bottrell HH, et al. (1976) A review of some problems in zooplankton production studies. Norw J Zool 24:419–456Google Scholar
  5. Burns CW, Schallenberg M (1996) Relative impact of cladocerans, copepods and nutrients on the microbial food web of a mesotrophic lake. J Plankton Res 18:683–714Google Scholar
  6. Carpenter SR, Kitchell JF, Hodgson DR (1985) Cascading trophic interactions and lake productivity. BioScience35:634–639Google Scholar
  7. DeMott WR (1986) The role of taste in food selection by freshwater zooplankton. Oecologia 69:334–340Google Scholar
  8. DeMott WR (1988) Discrimination between algae and artificial particles by freshwater and marine copepods. Limnol Oceanogr 33:397–408Google Scholar
  9. Doak DF, Bigger D, Harding EK, Marvier MA, O'malley RE, Thomson E (1998) The statistical inevitability of stability-diversity relationships in community ecology. Am Nat 151:264–276CrossRefGoogle Scholar
  10. Fussmann G (1996) Die Rolle der Rotatorien im Pelagial eines mesotrophen Sees durch Bottom-up und Top-down Prozesse: Freilandbeobachtungen und Enclosure-Experimente. Diploma thesis. University of Kiel, KielGoogle Scholar
  11. Geller W, Müller H. (1981) The filtration apparatus of cladocera: filter mesh sizes and their implications on food selectivity. Oecologia 49:316–321Google Scholar
  12. Gliwicz ZM (1980) Filtering rates, food size selection, and feeding rates in cladocerans – another aspect of interspecific competition in filter-feeding zooplankton. In: Kerfoot WC (ed) Evolution and ecology of zooplankton communities. University of New England Press, Hanover, N.H., pp 282–291.Google Scholar
  13. Hairston NG, Smith FE, Slobodkin LB (1960) Community structure, population control, and competition. Am Nat 94:421–425CrossRefGoogle Scholar
  14. Hillebrand H, Dürselen CD, Kischtel D, Pollingher U, Zohary T (1999) Biovolume calculations for pelagic and benthic microalgae. J Phycol 35:403–424CrossRefGoogle Scholar
  15. Hulot FD, Lacroix G, Lescher-Moutoué F, Loreau M (2000) Functional diversity governs ecosystem response to nutrient enrichment. Nature 405:340–344PubMedGoogle Scholar
  16. Jürgens K (1994) Impact of Daphnia on planktonic microbial food webs. A review. Mar Microb Food Webs 8:295–324Google Scholar
  17. Kiefer F (1978) Freilebende Copepoda. Die Binnengewässer, vol 26/2. Schweizerbarth, StuttgartGoogle Scholar
  18. Kleppel GS (1993) On the diet of calanoid copepods. Mar Ecol Prog Ser 99:183–195Google Scholar
  19. Lampert W (1978) Climatic conditions and planktonic interactions as factors controlling the regular succession of spring algal bloom and extremely clear water in Lake Constance. Verh Int Verein Limnol 20:969–974Google Scholar
  20. Lampert W (1988) The relationships between zooplankton biomass and grazing: a review. Limnologica 19:11–20Google Scholar
  21. Loreau M (2000) Biodiversity and ecosystem fuctioning: recent theoretical advances. Oikos 91:3–17Google Scholar
  22. McCann KS (2000) The diversity-stability debate. Nature 405:233CrossRefGoogle Scholar
  23. Naeem S, Li S (1997) Biodiversity enhances ecosystem reliability. Nature 390:507–509CrossRefGoogle Scholar
  24. Nalewajko C (1966) Dry weight, ash and volume data for some freshwater planktonic algae. J Fish Res Bd Can 23:1285–1287Google Scholar
  25. Oksanen L, Fretwell SD, Arruda J, Niemela P (1981) Exploitation ecosystems in gradients of primary productivity. Am Nat 118:240–261CrossRefGoogle Scholar
  26. Pace ML, Cole JJ, Carpenter SR, Kitchell JF (1999) Trophic cascades revealed in diverse ecosystems. Trends Ecol Evol 14:483–488PubMedGoogle Scholar
  27. Porter KG (1976) Enhancement of algal growth and productivity by grazing zooplankton. Science 192:1332–1334.Google Scholar
  28. Porter KG, Feig YS (1980) The use of DAPI for identifying and counting aquatic microflora. Limnol Oceanogr 25:943–947Google Scholar
  29. Power ME (1992) Top down and bottom up forces in food webs: do plants have primacy? Ecology 73:733-746Google Scholar
  30. Santer B (1990) Lebenszyklusstrategien cyclopoider Copepoden. PhD thesis. University of Kiel, KielGoogle Scholar
  31. Santer B (1994) Influences of food type and concentration on the development of Eudiaptomus gracilis and implications for the interactions between calanoid and cyclopoid copepods. Arch Hydrobiol 131:141–159Google Scholar
  32. Shapiro J, Wright DI (1984) Lake restoration by biomanipulation: Round Lake, Minnesota, the first two years. Freshwater Biol 14:371–383Google Scholar
  33. Sommer F, Stibor H, Sommer U, Velimirov B (2000) Grazing by mesozooplankton from Kiel Bight, Baltic Sea, on different sized algae and natural size fractions. Mar Ecol Prog Ser 199:43–53Google Scholar
  34. Sommer U, Stibor H (2002) Copepoda – Cladocera – Tunicata: the role of three major mesozooplankton groups in pelagic food webs. Ecol Res 17:161–174CrossRefGoogle Scholar
  35. Sommer U, Gliwicz ZM, Lampert W, Duncan A (1986) The PEG-model of seasonal succession of planktonic events in lakes. Arch Hydrobiol 106:433–471Google Scholar
  36. Sommer U, Sommer F, Santer B, Jamieson C, Boersma M, Becker C, Hansen T (2001) Complementary impact of copepods and cladocerans on phytoplankton. Ecol Lett 4:545–550CrossRefGoogle Scholar
  37. Steemann-Nielsen E (1952) The use of radioactive carbon (C-14) for measuring organic production in the sea. J Conserv Int Explor Mer 18:117-140Google Scholar
  38. Sterner RW (1989) The role of grazers in phytoplankton succession. In: Sommer U (ed) Plankton ecology. Succession in plankton communities. Springer, Berlin Heidelberg New York, pp 107–170Google Scholar
  39. Stoecker DH, Capuzzo JM (1990) Predation on protozoa and its importance to zooplankton. J Plankton Res 12:891–908Google Scholar
  40. Strong DR (1992) Are trophic cascades all wet? Differentiation and donor control in diverse ecosystems. Ecology 73:747–754Google Scholar
  41. Utermöhl H (1958) Zur Vervollkommnung der quantitativen Phytoplankton Methodik. Mitt Int Verein Limnol 9:1–39Google Scholar
  42. Yachi S, Loreau M (1999) Biodiversity and ecosystem productivity in a fluctuating environment: the insurance hypothesis. Proc Natl Acad Sci USA 96:1463–1468CrossRefPubMedGoogle Scholar

Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  • Ulrich Sommer
    • 1
  • Frank Sommer
    • 1
  • Barbara Santer
    • 2
  • Eckart Zöllner
    • 2
  • Klaus Jürgens
    • 2
  • Colleen Jamieson
    • 2
  • Maarten Boersma
    • 3
  • Klaus Gocke
    • 1
  1. 1.Institut für MeereskundeKielGermany
  2. 2.Max-Planck-Institut für LimnologiePlönGermany
  3. 3.Alfred-Wegener-InstitutBAHHelgolandGermany

Personalised recommendations