STOICHIOMETRIC COMPOSITION OF SESTON IN LITTORAL AND PELAGIAL ZONES OF SHALLOW LAKE OBSTERNO (BELARUS)

We estimated the seston elemental composition (C, N, P) and its ratio in pelagic and littoral zones of mesotrophic shallow Lake Obsterno during two contrasting seasons, as well as the influence of macrophyte beds on the seston stoichiometry. In the both pelagial and littoral zones in summer the C: N ratio was small, 4.62 and 7.05 respectively. But it increased slightly during autumn to 5.66 in pelagic samples against 8.33 in littoral ones. The large N : P ratio and the small phosphorus content specially in the macrophyte covered littoral zone equal to 57.7 in July against 22.47 in September suggest a high level of phosphorus limitation in the littoral locations as a possible mediated reason suppressing zooplankton abundance in sumabundance in sum in summer. Our results in the both pelagial and littoral habitat showed a highly P limited situation in which the N : P ratio was larger in littoral with macrophyte than in pelagial zones. The obtained data of littoral seston stoichiometry were recorded for the first time and exceeded the classical Redfield ratio. The elemental imbalance between macrophyte covered littoral and pelagial suggest that nutrients, especially P, are more limiting in macrophyte beds in summer due to the resource competition between phytoplankton and macrophytes for nutrients, a poor food quality, low zooplankton abundance, as well as its poor taxon-specific elemental ratio in summer.

seston, carbon, nitrogen, phosphorus, stoichiometry, littoral, pelagial, macrophyte beds

1. Andersen T., Hessen D. O. Carbon, nitrogen, and phosphorus content of freshwater zooplankton. Limnology and Oceanography, 1991, vol. 36, no. 4, pp. 807–814. https://doi.org/10.4319/lo.1991.36.4.0807

2. Hecky R. E., Campbell P., Hendzel L. L. The stoichiometry of carbon, nitrogen, and phosphorus in particulate matter

3. of lakes and oceans. Limnology and Oceanography, 1993, vol. 38, no. 4, pp. 709–724. https://doi.org/10.4319/lo.1993.38.4.0709

4. Redfield A. C. The biological control of chemical factors in the environment. American Scientist. 1958, vol. 46, pp. 205–221.

5. Sterner R. W., Andersen T., Elser J. J., Hessen D. O., Hood J. M., Mccauley E., Urabe J. Scale-dependent carbon:nitrogen:phosphorus seston stoichiometry in marine and freshwaters. Limnology and Oceanography, 2008, vol. 53, no. 3, pp. 1169–1180. https://doi.org/10.4319/lo.2008.53.3.1169

6. Otten J. H., Gons H. J., Rijkeboer M. Dynamics of phytoplankton detritus in a shallow, eutrophic lake (Lake Loosdrecht, The Netherlands). Hydrobiologia, 1992, vol. 233, no. 1–3, pp. 61–68. https://doi.org/10.1007/bf00016096

7. Sterner R. W., Schulz K. L. Zooplankton nutrition: recent progress and a reality check. Aquatic Ecology, 1998, vol. 32, no. 4, pp. 261–279. https://doi.org/10.1023/a:1009949400573

8. Sterner R. W. In situ-measured primary production in Lake Superior. Journal of Great Lakes Research, 2010, vol. 36, no. 1, pp. 139–149. https://doi.org/10.1016/j.jglr.2009.12.007

9. Guildford S. J., Hecky R. E. Total Nitrogen, Total Phosphorus and Nutrient Limitation in Lakes and Oceans: Is There a Common Relationship? Limnology and Oceanography, 2000, vol. 45, no. 6, pp. 1213–1223. https://doi.org/10.4319/lo.2000.45.6.1213

10. Schmidt K., McClelland J. M., Mente E., Montoya J. P., Atkinson A., Voss M. Trophic-level interpretation based on 15N values: implication of tissue-specific fractionation and amino acid composition. Marine Ecology Progress Series, 2004, vol. 266, pp. 43–58. https://doi.org/10.3354/meps266043

11. Urabe J. Direct and indirect effects of zooplankton on seston stoichiometry. Ecoscience, 1995, vol. 2, no. 3, pp. 286–296. https://doi.org/10.1080/11956860.1995.11682296

12. Dobberfuhl D. R., Elser J. J. Use of dried algae as a food source for zooplankton growth and nutrient release experiments. Journal of Plankton Research, 1999, vol. 21, no. 5, pp. 957–970. https://doi.org/10.1093/plankt/21.5.957

13. Urabe J., Watanabe Y. Possibility of N or P limitation for planktonic cladocerans: An experimental test. Limnology and Oceanography, 1992, vol. 37, no. 2, pp. 244–251. https://doi.org/10.4319/lo.1992.37.2.0244

14. Sterner R. W., Hagemeier D. D., Smith W. L., Smith R. F. Phytoplankton nutrient limitation and food quality for Daphnia. Limnology and Oceanography, 1993, vol. 38, no. 4, pp. 857–871. https://doi.org/10.4319/lo.1993.38.4.0857

15. DeMott W. R. Utilization of a cyanobacterium and a phosphorus-deficient green alga as complementary resources by daphnids. Ecology, 1998, vol. 79, no. 7, pp. 2463–2481. https://doi.org/10.1890/0012-9658(1998)079[2463:uoacaa]2.0.co;2

16. Elser J. J., Hassett R. I. A stoichiometric analysis of zooplankton-phytoplankton interactions in marine and freshwater ecosystems. Nature, 1994, vol. 370, pp. 211–213. https://doi.org/10.1038/370211a0

17. Hessen D. O. Factors determining the nutritive status and production of zooplankton in humic lake. Journal of Plankton Research, 1989, vol. 11, no. 4, pp. 649–664. https://doi.org/10.1093/plankt/11.4.649