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The Eutrophication Problem in Temperate Lakes: Practical Aspects and Theoratical ...
Chapter 6 presents several examples of how the minimal model of
pelagic nutrient cycling can be extended stepwise toward a closer resemblance to a real pelagic food web. The base of the food web is widened by
introducing new algal species with different competitive abilities and different edibilities to the zooplankton. The interaction of two different nutrient cycles is studied by introducing nitrogen as a second, potentially limiting nutrient. Carbon cycling is represented by introducing detritus as an
alternate food source to the zooplankton. The interaction of carbon and
nutrient cycling is studied by introducing bacteria as both competitors for
mineral nutrients and as salvagers of detritus carbon. The effect of each
extension is compared to the minimal model in Chapter 5, with special
emphasis on the possible emergence of new modes of dynamic behavior as
the number of state variables is increased.
A short concluding chapter then tries to summarize the major results of
the preceding ones, and also discuss some of the limitations and omissions
in the models. In order to test model predictions and improve on model
limitations, several directions for future research are suggested.