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Nutrients. Algae and Herbivores - the Paradox of Enrichment Revisited
When the P loading conditions in the present model are such that both
the dilution rate is below the persistence boundary and input concentration
is above the threshold for positive zooplankton biomass, both the stationary points at the C axis (the washout point and the grazer extinction point)
will be saddle points in the sense that they have two negative and one positive eigenvalues (cf. Appendix A6). In addition to the two unstable saddle
points, we will also have a stable equilibrium at the internal focus. From
Fig. 5.7, we can see that trajectories approaching the unstable washout
point at the origin will be repelled along the C axis, while trajectories
Fig. S.8A,B. Outstructure geometry of the stationary points at A low P loading, and B high P
loading. Directed paths State trajectories; filled circles locally stable stationary points; open
circles locally unstable stationary points
Nutrients. Algae and Herbivores - the Paradox of Enrichment Revisited
When the P loading conditions in the present model are such that both
the dilution rate is below the persistence boundary and input concentration
is above the threshold for positive zooplankton biomass, both the stationary points at the C axis (the washout point and the grazer extinction point)
will be saddle points in the sense that they have two negative and one positive eigenvalues (cf. Appendix A6). In addition to the two unstable saddle
points, we will also have a stable equilibrium at the internal focus. From
Fig. 5.7, we can see that trajectories approaching the unstable washout
point at the origin will be repelled along the C axis, while trajectories
Fig. S.8A,B. Outstructure geometry of the stationary points at A low P loading, and B high P
loading. Directed paths State trajectories; filled circles locally stable stationary points; open
circles locally unstable stationary points