The maintenance of ecosystems provides a basis for the protective, productive and recreational functions of forests, and however society may wish to utilise the forest, the survivability and interrelationship between all life forms within the forest ecosystem provides the foundation for all the other functions of the forest. The preservation, and if necessary the restoration, of the ecosystem is, therefore, the first priority.

The elements of ecosystem functionality are:

• Local and regional diversity of flora and fauna (species diversity)
• Genetic diversity within the local population of each species, providing the potential for evolutionary development (genetic diversity)
• Species diversity as well as genetic diversity ensure the ability to adapt to climate change.
• Local and regional diversity of ecosystems (spatial and temporal diversity in structure)
• The occurrence of ecological processes (natural and semi-natural forest dynamics)
• The ecological network
• The ecological interactions of forests in relation to the environment (world-, regional- and local climate, and interaction with surrounding landscape).

PRO SILVA recommends the following essential methods to allow forest ecosystems to function:

• Paying serious attention to (i.e. maintaining or restoring) the natural forest vegetation pattern, while making use of the forest;
• Maintenance of soil productivity, through continuous cover and through the maintenance of biomass in the forest (including dead wood);
• Propagation of mixed forest with special attention to rare and endangered species;
• Restricting the use of exotics to cases where this is an economic necessity, and then only if the exotics can be mixed with the indigenous vegetation pattern within certain quantitative and qualitative limits;
• In special cases, forgo any harvest.

The elements of the conservation of forest ecosystems, as stated above, correspond to the declaration on biodiversity which was made at the Rio conference in 1992. The protection, production and recreational functions of the forest are all based on the conservation of the ecosystem; and they are all, in their own way, important to society.