Tune unstructured resources (algae and detritus) to steady state

This first sets the algae biomass so that, for the given abundances and the algae's fixed production rate (see getAlgaeProduction()), algae is at steady state. It then sets the rate at which detritus flows in from external sources (e.g. the pelagic zone) so that for the given abundances the detritus is at steady state.

Usage

tuneUR(params, ...)

Arguments

params

A MizerParams object

...

unused

Value

An updated MizerParams object

Details

The time evolution of the algae biomass \(B_A(t)\) is described by \(dB_A/dt = P_A - c_A \cdot B_A\), where \(c_A\) is the mass-specific consumption rate from algae_consumption() and \(P_A\) is the algae production rate from getAlgaeProduction(). Unlike detritus, algal production on a reef is primary production, not driven by consumer demand: \(P_A\) is a fixed property of the algae, left unchanged by this function. Instead, this tuning function solves \(dB_A/dt = 0\) for the algae biomass, setting it to \(B_A = P_A / c_A\). This means that, all else equal, a decrease in grazing pressure (lower \(c_A\)) increases the tuned algae biomass rather than reducing \(P_A\) to compensate. If \(c_A = 0\) (no consumers), no finite steady-state biomass exists and the algae biomass is left unchanged, with a warning.

See also

reefSteady(), algae_dynamics(), detritus_dynamics()

Examples

data(caribbean_3_model)
params <- tuneUR(caribbean_3_model)
#> Warning: The flux of external detritus is negative.