The paper deals with the application of forest dynamics. Reference is made to two studies, which have been carried out at a national level. The simulations of forest decline as well as the production of exceedingly thick timber of spruce and fir provide various examples of the major problems of forest simulation and of some possible solutions. It is pointed out that the statistical analysis of empirical data is most important for modelling and it might bring about even more valuable results than the ultimate simulation itself.
While the most common type of mycorrhizae is endomycorrhizae, ectomycorrhizae dominate in the case of coniferous trees. Pine, in particular, has a strong association with mycorrhizae. Mycorrhizae enable trees to take up water and nutrients much more efficiently than the roots themselves. The fungus, in return, obtain carbohydrates and is able to grow and fruit. Mycorrhizal fungi are probably numbered in their thousands but so far few are known. Knowledge about their physiology, in particular, is lacking and studies dealing with their isolation and inoculation, which may be commercially valuable, remain unpublished. A new challenge for mycorrhiza research is the effects of air pollution. Forest suffering from extensive air pollution have few mycorrhizal fungi., infection is weak and the number of root deformations is high. As good mycorrhizae are important to tree health, there is a particular need to intensify mycorrhiza research.
The PDF includes an abstract in English.