SORTIEND
Software for spatiallyexplicit simulation of forest dynamics 

Absolute growth behaviorsSeveral behaviors apply an absolute growth version of the MichaelisMenton function. Parameters for these behaviors
Absolute growth is calculated with the equation: where
Amount of diameter growth per timestep is calculated as where T is the number of years per timestep. The absolute growth behaviors also take into account suppression status. A tree is considered suppressed if its growth rate for the previous timestep falls below a certain threshold. That threshold is the rate of growth at which X% of juveniles die, where X is a usersettable parameter. The threshold is calculated for each species by solving the BC mortality equation for G (growth), where m is the threshold growth rate. A tree's suppression state is a multiplicative factor in its growth rate. If a tree is not suppressed, the suppression factor in the growth equation is set to 1 (no effect on growth). If the tree is suppressed, the suppression factor is calculated as follows: where:
Details of this model are published in Wright et al 2000. Absolute growth limited to radial incrementHow it worksThis behavior calculates an amount of diameter growth according to the absolute growth equation. Growth is limited to a maximum of the constant radial increment for the species of tree to which it is being applied. The increment is calculated as described in the "Constant radial growth" behavior. Note that the increment parameter specifies radial growth; the behavior makes all necessary conversions. How to apply itThis behavior 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 light behavior applied. You can use either the diam with auto height or diam only version. Absolute growth limited to basal area incrementHow it worksThis behavior calculates an amount of diameter growth according to the absolute growth equation. Growth is limited to a maximum of a constant basal area increment. The amount of diameter increase is calculated by dividing the annual basal area increment of the tree's species by the diameter of the tree. The increment is calculated as described in the "Constant basal area growth" behavior. How to apply itThis behavior 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 light behavior applied. You can use either the diam with auto height or diam only version. Nonlimited absolute growth  diam with auto heightHow it worksThe amount of diameter increase returned by the absolute growth equation is applied to the tree.How to apply itThis behavior 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 light behavior applied. You can use either the diam with auto height or diam only version. 

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