SORTIE-ND
Software for spatially-explicit simulation of forest dynamics

Browsed Stochastic Mortality

This simulates the effects of herbivory by allowing different background mortality rates for browsed and unbrowsed trees.

Trees killed by this behavior will have a mortality reason code of "natural".

Parameters for this behavior

Parameter nameDescription
Background Mortality RateThe proportion of trees that die each year, as a value between 0 and 1.
Browsed Background Mortality RateThe proportion of browsed trees that die each year, as a value between 0 and 1.

How it works

Whether or not a tree is browsed is determined by the Random browse behavior. For each tree, if it has not been browsed, that species's Background Mortality Rate parameter is used; if it has been browsed, the species's Browsed Background Mortality Rate parameter is used. A random number is compared to the appropriate rate to decide if the tree dies.

How to apply it

This 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 the Random browse behavior applied.