Early pioneer plants do reestablish under bad conditions and eventually lead to climax growth. Over a few decades biomass recovers to climax levels. Light and genetics turn out to be the limiting factors to plant growth, not nutrient soil depletion, due to intensive recycling in even semi-mature forests. The model does not include the potential effects of increased concentration of atmospheric carbon dioxide on photosynthesis and growth rates. Decay time for organic material is defined at 1 year.
Nutrient availability is defined as a ratio between decomposition and unlimited growth.
The limiting factors on unconstrained growth in this ecosystem are light and genetics. Plants need light to grow and are genetically programmed to reach only a certain height. The model of the global carbon cycle deals with the forces that act on carbon as it circulates between reservoirs. The reservoirs of carbon are the earth, the biosphere, the atmosphere and the ocean. The model should show how what happens to the carbon dioxide temissions in the atmospher from fossil fuel burning and deforestation.