One of the most important objectives of PROSILVA is the preservation and development of all values of the forest, including the value of the forest to society and its intrinsic value. An important part of this value is the full spectrum of life forms and organisms of the forest ecosystem.
These various organisms and life forms are associated with the different development and successional phases of the forest, including degradation phases, open areas, standing and flowing water, and others. The totality of all organisms living in a particular forest ecosystem is a reflection of its specific biodiversity, being a part of the broader concept of global biodiversity.
Biodiversity includes higher and more primitive plant and animal species, whether or not they have a commercial value or use to society.
The preservation of species diversity as part of global biodiversity, is regarded as a prime function of the forest. This is the case irrespective of any recognisable link with human needs.
The preservation of species diversity has, in addition to its intrinsic value, considerable relevance to the use of the forest ecosystem by society. Beside the traditional use of timber and many other forest products, one should keep in mind potential products which might have a market value in the future.
In addition, it is important to note that the preservation of biodiversity generally results in a reduction of ecological and economic risks.
- Use of indigenous tree species: because numerous animal and plant species are connected to the indigenous trees in their co-evolutionary development;
- Enhancement of diversity in forest structure through forest regeneration, tending and exploitation as a means of obtaining appropriate occurrence of niches in space and time;
- Acceptance of standing and fallen dead trees, hollow trees, old groves, etc. in sufficient quantities and distribution;
- Protection of special biotopes in the forest (wetlands, rocky outcrops, dunes, etc.);
- Regulation of unnaturally high game densities, and other populations of herbivores which over-use the forest over large areas.
Conservation of biodiversity must be included and facilitated within the medium-term management plans.