Forest life and its temporal uncertainty

During its growth a forest is exposed to numerous abiotic and biotic calamities. Each of them has its own temporal trend but generally the adverse effect increases with age. This fact decreases the certainty of forest production with age and increases the risk involved in forest management. The uncertainty at a given age can be expressed with the aid of the theory of random,processes by the probability of destruction of a forest stand or an age class. The destruction rate can-be expressed similarly. The focus of the present article is on estimation of the mean number of years of future forest life in correlation to the current age. The WEIBULL distribution function is used to describe the reliability. The studied processes are also described in a discrete form by absorbtion MARKOV chains. In addition, the effects of individual harmful factors can be assessed. A forest life table analogous to fife tables for human populations is an important result of the paper. Application of the fife tables to forest management and forest insurance mathematics is discussed.