System Dynamics

LogisticGrowth Block

Models population growth that is limited by a carrying capacity (resources).

Open LogisticGrowth in BlockWerk →

Description

The Logistic Growth model describes population growth that is limited by a carrying capacity. Unlike exponential growth (which grows forever), logistic growth slows down as the population approaches the environment's resource limit.

Mathematical Model

\frac{dP}{dt} = r P \left(1 - \frac{P}{K}\right)

The change in population $P$ over time is governed by the logistic equation:

$$\frac{dP}{dt} = r \cdot P \cdot \left(1 - \frac{P}{K}\right)$$

Where:

At small $P$, the term $(1 - P/K)$ is close to 1, and the population grows exponentially. As $P$ approaches $K$, the term $(1 - P/K)$ approaches 0, and the growth stops.

Parameters

growthRate ($r$)

The per-capita growth rate when resources are unlimited.

carryingCapacity ($K$)

The maximum population that can be supported by the environment.

initialPopulation

The starting population size at the beginning of the simulation.

Ports

population (Output)

The current population size.

Examples

Remarks

See Also