Educational Model: Logistic Growth
The model demonstrates patterns of logistic population growth.
This model is a component of the IUMC (Innovative Educational and Methodological Complex) "Ecology: Constructing the Biosphere," developed in 2008 by D. A. Shabanov, A. G. Kozlenko, and M. A. Kravchenko by order of the NTFP (National Training Foundation) of the Russian Federation. The model is posted for educational use. The model demonstrates patterns of logistic population growth. The theoretical material is in the section "Exponential and Logistic Population Growth" of the manual "Ecology: Biology of Interactions." In this version, logistic growth is described by dN/dt = r×N - (r/K)×N^2, equivalent to dN/dt = r×N×(K-N)/K. Here dN/dt is change in abundance per unit time, N is abundance, r is the growth-rate coefficient, and K is carrying capacity. By changing controlled parameters, users can study their effects on abundance dynamics in a freely reproducing population limited by resource shortage, and examine disturbances (sharp decline or surge in abundance). Instructions are located at the bottom of the model window; if they do not fit, scroll using the arrows on the right. Some tasks: (1) Analyze the influence of each parameter on abundance dynamics. (2) Which natural or laboratory factors can limit abundance, and through which mechanisms?