Nutrient Element Limitation of Zooplankton Production

Freshwater crustacean zooplankton species show pronounced interspecific variability but approach intraspecific homeostasis in their stoichiometry. It is especially interesting that members of the dominating herbivores in freshwater systems, such as Daphnia species, show consistently high P:C ratios. Sestonic P:C ratios in epilimnetic waters are usually far below that encountered in the zooplankton, which suggests that grazers may approach a direct phosphorus limitation in many localities. This view was supported by a regional study of 47 lakes, in which most independent variables including phytoplankton biomass and chlorophyll were scarcely correlated with zooplankton biomass but particulate P (>0.45 μm) could explain a major part of the variance of zooplankton biomass. Of the various taxa, daphnids gave the best correlation with particulate P, cyclopids and rotifers the worst. These observations suggest that phytoplankton biomass per se may not be the major determinant of zooplankton biomass but that the nutritional status of phytoplankton (P cell quotas) rather than biomass in terms of carbon is most important, or that zooplankton suffer a direct P limitation in many lakes. The latter view is supported by model predictions given in this article. Also, both freshwater and marine copepod grazers could correspondingly be growth limited by an N:C ratio of ingested food that is too low The possibility of direct nutrient element limitation has wide implications for the regulation of herbivore production, competition, and overall cycling of nutrients in epilimnetic waters.

[1]  H. Bottrell.  A review of some problems in zooplankton production studies , 1976 .

[2]  E. Orskov.  Protein nutrition in ruminants , 1982 .

[3]  K. Børsheim,et al.  Dependence of the rate of release of phosphorus by zooplankton on the P: C ratio in the food supply, as calculated by a recycling model1 , 1986 .

[4]  R. Sterner.  The Ratio of Nitrogen to Phosphorus Resupplied by Herbivores: Zooplankton and the Algal Competitive Arena , 1990, The American Naturalist.

[5]  A. J. Tessier,et al.  Starvation in Daphnia: Energy reserves and reproductive allocation1 , 1983 .

[6]  N. Yan.  Empirical Prediction of Crustacean Zooplankton Biomass in Nutrient-Poor Canadian Shield Lakes , 1986 .

[7]  R. D. Gulati.  Carbon and phosphorus relationships of zooplankton and its seston food in Loosdrecht Lakes , 1991 .

[8]  Gregory A. Lang,et al.  Dynamics of Lake Michigan Plankton: A Model Evaluation of Nutrient Loading, Competition, and Predation , 1988 .

[9]  K. Porter.  Selective Grazing and Differential Digestion of Algae by Zooplankton , 1973, Nature.

[10]  Ulrich Sommer,et al.  Plankton ecology, succession in plankton communities , 1989 .

[11]  D. Jenkinson.  The Nitrogen Cycle in Long-Term Field Experiments , 1982 .

[12]  M. Pace.  An empirical analysis of zooplankton community size structure across lake trophic gradients1 , 1986 .

[13]  W. Lampert,et al.  Simultaneous measurement of food concentration on carbon assimilation and respiration in Daphnia magna , 1988 .

[14]  D. S. Rawson.  The Standing Crop of Net Plankton in Lakes , 1953 .

[15]  O. Ravera,et al.  WEIGHT, SIZE, AND CHEMICALC OMPOSITION OF SOME FRESHWATER ZOOPLANKTERS: DAPHNIA HYALINA( LEYDIG)1 , 1972 .

[16]  R. Sterner,et al.  Phytoplankton nutrient limitation and food quality for Daphnia , 1993 .

[17]  T. Andersen,et al.  Carbon metabolism in a humic lake: Pool sires and cycling through zooplankton , 1990 .

[18]  Edward McCauley,et al.  Empirical Relationships Between Phytoplankton and Zooplankton Biomass in Lakes , 1981 .

[19]  R. Peters.  Methods for the Study of Feeding , Grazing and Assimilation by Zooplankton , 2022 .

[20]  W. Gabriel,et al.  Tracer kinetics in Daphnia: an improved two-compartment model and experimental test , 1984 .

[21]  D. O. Hessen,et al.  Carbon, nitrogen and phosphorus status in Daphnia at varying food conditions , 1990 .

[22]  Dag O. Hessen,et al.  Inter- and intraspecific variations in zooplankton element composition , 1991, Archiv für Hydrobiologie.

[23]  Yasunori Watanabe.  C: N: P ratios of size-fractionated seston and planktonic organisms in various trophic levels , 1990 .

[24]  J. Downing,et al.  A Manual on Methods for the Assessment of Secondary Productivity in Fresh Waters , 1984 .

[25]  Tom Andersen,et al.  Carbon, nitrogen, and phosphorus content of freshwater zooplankton , 1991 .

[26]  R. Hecky,et al.  Nutrient limitation of phytoplankton in freshwater and marine environments: A review of recent evidence on the effects of enrichment1 , 1988 .

[27]  David Tilman,et al.  Resources: A Graphical-Mechanistic Approach to Competition and Predation , 1980, The American Naturalist.

[28]  O. Vadstein,et al.  Chemical composition and phosphate uptake kinetics of limnetic bacterial communities cultured in chemostats under phosphorus limitation , 1989 .