But when tropical vegetation is razed or burned, the soil can no longer regenerate itself. The ecosystem suffers, especially as the reduction of the plant cover creates runoffs and gullies, depleting the soil layer even more. It affects both natural habitats and the areas exploited by man. In the sea, the coral reefs, home to an extraordinary variety of plants and animals, are seriously endangered. This typifies the fundamental problem with biodiversity.
People see it as communal property which anyone can use.
But an ecosystem is an organic chain. Not to mention human beings, who collect firewood, food and medicinal herbs from the forest. None of this appears in the countries' figures. They only show the biodiversity assets, the financial yield from exploitation, not the liabilities or losses. Of course the idea of sustainable development is starting to catch on, but it has not yet been accepted in poor countries, with urgent needs which often force them to sacrifice their capital.