Ecosystem Terrarium: Closed-Loop Population Dynamics and Water Cycle

Overview of Ecosystem Dynamics

The Ecosystem Terrarium is a sophisticated simulation that models a two-dimensional closed-loop environment. This terrarium includes plant growth limited by the Monod model, where resource availability affects population dynamics. Herbivores graze on plants following Holling type-II predation theory, which describes how predators consume prey at a rate proportional to their encounter with prey.

Decomposers recycle nutrients back into the soil, and a closed water cycle ensures that evaporation and condensation maintain moisture levels within the terrarium. This simulation integrates these processes using the Runge-Kutta 4th order (RK4) method across six coupled state variables.

Key Components of the Simulation

The Monod model is a mathematical framework that describes how resource availability limits population growth. It assumes that there is an optimal concentration of resources for maximum growth, and as this concentration decreases below or above the optimum, growth rates decline.

Holling type-II predation theory models the rate at which predators consume prey based on their encounter rate with prey. This model predicts a sigmoidal relationship between predator consumption and prey density.

Importance of Closed-Loop Systems

Understanding closed-loop ecosystems is crucial for studying ecological interactions in real-world scenarios, such as agricultural systems, natural reserves, and urban green spaces. The terrarium simulation helps elucidate how different factors interact to maintain ecosystem stability.

By manipulating variables like light intensity, day length, herbivore presence, grazing rates, decomposition rates, and soil moisture, students can observe the impact of these changes on the overall health and dynamics of the ecosystem.

Real-World Applications

The principles underlying this terrarium model are applicable to a wide range of ecological studies. For instance, it can be used to predict how climate change might affect plant growth in different regions or how changes in grazing patterns impact grassland ecosystems.

Additionally, the simulation aids in understanding nutrient cycling and water management strategies in agricultural systems, helping to develop sustainable practices that minimize environmental impact.

Frequently asked questions

Try it live

Everything above runs in your browser — open Ecosystem Terrarium: Closed-Loop Population & Water Cycle (2D) and change the parameters while it is running. Nothing is installed, nothing is uploaded, the whole model lives in one tab.