Reforestation is a term that means the process by which an area devoid of vegetation for a long time or previously wooded area is covered by trees suitable to that area. It is therefore a change of use of the soil. Reforestation can be artificial, if done by man, or if it just happens naturally, thanks to the seeds carried by wind or animals. In the latter case we speak more properly of forest colonization.
The difference between reforestation and afforestation is that the first process takes place on land where the forest was present up to age more or less recently, while speaking of planting when the process takes place in wooded land never previously wooded or never in living memory of a man.
Reforestation should not be confused with the renewal of the forest, ie the growth of new seedlings in woodland, where trees have been cut by man or destroyed by natural disasters. In this case there is no change of intended use of the soil, but merely to preserve the status quo. The renewal of the forest may be artificial, if carried to humans by seeding or planting, or natural, if it occurs naturally from the seeds of the trees remained.
The forest is able to significantly influence the biosphere and the economic structure of a region at different levels and in different areas. Therefore, the purposes of afforestation can be as diverse as:
- slowing soil erosion;
- raising the level of groundwater aquifers in the area;
- restoration of biodiversity;
- constraints on the possible process of desertification;
- protection against floods or avalanches;
- timber production;
- control of the content of carbon dioxide in the atmosphere.
In the long term, afforestation is justified by considerations of environmental sustainability and sustainable development. Such projects could be used to help address the greenhouse effect.
The reforestation process can be facilitated by avoiding or simply by controlling the conditions unfavorable to the development of a forest. Otherwise, actively intervening, one of the main difficulties is to choose the most suitable seeds and to ensure germination.