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Unsaturated fatty acid content in seston and tropho-dynamic coupling in lakes


Determining the factors that control food web interactions is a key issue in ecology1,2. The empirical relationship between nutrient loading (total phosphorus) and phytoplankton standing stock (chlorophyll a) in lakes was described about 30 years ago3 and is central for managing surface water quality. The efficiency with which biomass and energy are transferred through the food web and sustain the production of higher trophic levels (such as fish) declines with nutrient loading and system productivity4,5, but the underlying mechanisms are poorly understood. Here we show that in seston (fine particles in water) during summer, specific ω3-polyunsaturated fatty acids (ω3-PUFAs), which are important for zooplankton6,7,8,9,10, are significantly correlated to the trophic status of the lake. The ω3-PUFAs octadecatetraenoic acid, eicosapentaenoic acid (EPA) and docosahexaenoic acid, but not α-linolenic acid, decrease on a double-logarithmic scale with increasing total phosphorus. By combining the empirical relationship between EPA-to-carbon content and total phosphorus with functional models relating EPA-to-carbon content to the growth and egg production of daphnids8, we predict secondary production for this key consumer. Thus, the decreasing efficiency in energy transfer with increasing lake productivity can be explained by differences in ω3-PUFA-associated food quality at the plant–animal interface.

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  1. 1

    Matson, P. A. & Hunter, M. D. (eds) The Relative Contribution of Top-Down and Bottom-Up Forces in Population and Community Ecology (Special Feature Ecology 73, Ecological Society of America, 1992)

  2. 2

    Polis, G. A. & Winemiller, K. O. (eds) Food Webs: Integration of Pattern and Dynamics (Chapman & Hall, New York, 1996)

  3. 3

    Vollenweider, R. A. Advances in defining the critical loading levels for phosphorus in lake eutrophication. Mem. Ist. Ital. Idrobiol. 33, 53–83 (1976)

  4. 4

    Carpenter, S. R. & Kitchell, J. F. Plankton community structure and limnetic primary production. Am. Nat. 124, 159–172 (1984)

  5. 5

    McQueen, D. J., Post, J. R. & Mills, E. L. Trophic relationships in freshwater pelagic ecosystems. Can. J. Fish. Aquat. Sci. 43, 1571–1581 (1986)

  6. 6

    Jónasdóttir, S. H., Fields, D. & Pantoja, S. Copepod egg production in Long Island Sound USA, as a function of the chemical composition of seston. Mar. Ecol. Prog. Ser. 119, 87–98 (1995)

  7. 7

    Müller-Navarra, D. C. Evidence that a highly unsaturated fatty acid limits Daphnia growth in nature. Arch. Hydrobiol 132, 297–307 (1995)

  8. 8

    Müller-Navarra, D. C., Brett, M. T., Liston, A. M. & Goldman, C. R. A highly unsaturated fatty acid predicts carbon transfer between primary producers and consumers. Nature 403, 74–77 (2000)

  9. 9

    Ravet, J. L., Brett, M. T. & Müller-Navarra, D. C. A test of the role of polyunsaturated fatty acids in phytoplankton food quality for Daphnia using liposome supplementation. Limnol. Oceanogr. 48, 1938–1947 (2003)

  10. 10

    Brett, M. T. & Müller-Navarra, D. C. The role of highly unsaturated fatty acids in aquatic food-web processes. Freshwat. Biol 38, 483–499 (1997)

  11. 11

    Brett, M. T. & Goldman, C. R. Consumer versus resource control in freshwater pelagic food webs. Science 275, 384–386 (1997)

  12. 12

    Micheli, F. Eutrophication, fisheries, and consumer–resource dynamics in marine pelagic ecosystems. Science 285, 1396–1398 (1999)

  13. 13

    McQueen, D. J., Johannes, M. R. S., Post, J. R., Stewart, T. J. & Lean, D. R. S. Bottom-up and top-down impacts on freshwater pelagic community structure. Ecol. Monogr. 59, 289–309 (1989)

  14. 14

    Müller-Navarra, D. C. & Lampert, W. Seasonal patterns of food limitation in Daphnia galeata: separating food quantity and quality effects. J. Plankton Res. 18, 1137–1157 (1996)

  15. 15

    Sommer, U., Gliwicz, Z. M., Lampert, W. & Duncan, A. The PEG-model of seasonal succession of planktonic events in fresh waters. Arch. Hydrobiol. 106, 433–471 (1986)

  16. 16

    Schindler, D. W. Detecting ecosystem response to anthropogenic stress. Can. J. Fish. Aquat. Sci. 44, 6–25 (1987)

  17. 17

    DeMott, W. R. & Tessier, A. J. Stoichiometric constraints vs. algal defenses: Testing mechanisms of zooplankton food limitation. Ecology 83, 3426–3433 (2002)

  18. 18

    Elser, J. J., Chrzanowski, T. H., Sterner, R. W. & Mills, K. H. Stoichiometric constraints on food-web dynamics: a whole-lake experiment on the Canadian Shield. Ecosystems 1, 120–136 (1998)

  19. 19

    Sterner, R. W. & Elser, J. J. (eds) Ecological Stoichiometry. The Biology of Elements from Molecules to the Biosphere (Princeton Univ. Press, Princeton, NJ, 2003)

  20. 20

    Sterner, R. W., Elser, J. J., Fee, E. J., Guildford, S. J. & Chrzanowski, T. H. The light:nutrient ratio in lakes: the balance of energy and materials affects ecosystem structure and process. Am. Nat. 150, 663–684 (1997)

  21. 21

    Gulati, R. D., Lammens, E. H. R. R., Meier, M.-L. & Van Donk, E. Biomanipulation—tool for water management. Hydrobiologia 200/201, (1990)

  22. 22

    Ahlgren, G. Seasonal variation of fatty acid content in natural phytoplankton in two eutrophic lakes. A factor controlling zooplankton species? Verh. Int. Verein. Limnol. 25, 144–149 (1993)

  23. 23

    Ahlgren, G., Goedkoop, W., Markensten, H., Sonesten, L. & Boberg, M. Seasonal variations in food quality for pelagic and benthic invertebrates in Lake Erken—the role of fatty acids. Freshwat. Biol 38, 555–570 (1997)

  24. 24

    Ahlgren, G., Sonesten, L., Boberg, M. & Gustafsson, I.-B. Fatty acid content of some freshwater fish in lakes of different trophic levels—a bottom-up effect? Ecol. Freshwat. Fish 5, 15–27 (1996)

  25. 25

    Arts, M., Ackman, R. G. & Holub, B. J. Essential fatty acids in aquatic ecosystems: a crucial link between diet and human health and evolution. Can. J. Fish. Aquat. Sci. 58, 122–137 (2001)

  26. 26

    Wang, K. S. & Chai, T. Reduction in ω3 fatty acids by UV-B irradiation in microalgae. J. Appl. Phycol. 6, 415–421 (1994)

  27. 27

    Greenberg, A. E., Trussel, R. R., Clesceri, L. S. & Franson, M. A. H. (eds) Standards and Methods for the Examination of Waters and Wastewaters (United Book, Baltimore, 1995)

  28. 28

    Marker, A. F., Crowther, C. A. & Gunn, R. J. M. Methanol and acetone as solvents for estimating chlorophyll-a, and phaeopigments by spectrophotometry. Arch. Hydrobiol. Beih. Ergebn. Limnol. 14, 52–69 (1980)

  29. 29

    Kattner, G. & Fricke, H. S. G. Simple gas–liquid chromatographic method for the simultaneous determination of fatty acids and alcohols in wax esters of marine organisms. J. Chromatogr. 361, 263–268 (1986)

  30. 30

    Mardia, K. V., Kent, J. T. & Bibby, J. M. (eds) Multivariate Analysis (Academic, London, 1978)

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We thank A. Liston for assistance; U. Müller, D. Hunter and A. Makulla for phytoplankton counts; and G. Malyj for editing the manuscript. This study was funded by a US National Science Foundation grant to M.T.B., C.R.G. and D.C.M.-N.

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Correspondence to Dörthe C. Müller-Navarra.

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The authors declare that they have no competing financial interests.

Supplementary information

Supplementary Table: Characteristics of the lakes sampled. (DOC 12 kb)

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Figure 2: Regressions between lake TP concentration and sestonic EPA and DHA.
Figure 1: Regressions between lake TP concentration and sestonic ω3-PUFA-to-C contents.
Figure 3: Calculation of the growth rates and egg production of Daphnia magna.
Figure 4: First canonical pattern.


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