SORTIE-NDSoftware for spatially-explicit simulation of forest dynamics
Allometric diameter and height growth
How it works
These behaviors are designed to be secondary growth behaviors. If you have a behavior that primarily updates one tree dimension (diameter or height), one of these behaviors can be used on the other dimension to ensure even growth. These behaviors calculate a growth amount based on the allometry equations. The amount of growth is:
where Y is the amount of growth calculated by this behavior, f(X) is the allometry equation relating diameter and height, X t is the other tree dimension (either height or diameter) before the primary growth is applied, and X t+1 is the other tree dimension after primary growth is applied. The allometric diameter growth behavior can be paired with any height-only growth behavior, and the allometric height growth behavior can be paired with any diam-only growth behavior.
How to apply it
These behaviors can be applied to seedlings, saplings, and adults of any species. Any tree species/type combination to which it is applied must also have a growth behavior applied that grows the opposite tree dimension.