There is between one-third and one-half less forest on Earth today. And in recent times, what remains has been disappearing at an alarming rate.
Each year, 13 million hectares of forest is lost, according to 2005 figures. That's an area roughly the size of Nova Scotia and New Brunswick combined.
When forest regeneration is taken to account, the net annual loss is still 7.3 million hectares, the UN Food and Agriculture Organization reports. (Some environmental groups, though, dispute this number as being too low.)
In addition to its obvious negative effects on forest eco-systems, deforestation also contributes to climate change:
The major loci of deforestation are mainly in the Third World, as land is cleared for agriculture, oil production (ironic, huh?), and obviously for logging. The article states that Canada has put a halt to deforestation, and in much of the developed world, the trends have even reversed, with Europe adding 661,000 hectares of forest per year. And there are some signs of progress elsewhere as well:
When forests are cleared in a non-sustainable way, the environment receives a nasty double-whammy.
The cleared forests can't take any carbon dioxide out of the air, which means less of a filter for greenhouse gas emissions.
But the act of deforestation actually is a major cause of those emissions as well. Moist, dense rainforest soil contains even more carbon than the tree branches and leaves, and it's all released into the atmosphere when the forest is cut and burned.
The clearing of forests has helped Indonesia become the third-largest producer of greenhouse gases on the planet. Brazil is close behind.
And deforestation contributes roughly 25 per cent of the world's greenhouse gas emissions, according to various estimates.
That's more than 12 times all of Canada's emissions or, as one British newspaper theorizes, the equivalent of eight million people flying from London to New York daily.
China, as well, added almost four million hectares of forest cover each year during the first half of the decade. Vietnam is adding two per cent annually.
And as awareness of the problem grows, countries are setting aside more land for conservation. The central African country of Gabon, to name one example, set aside 10 per cent of its forest land in 2005.
The UN has an initiative to plant 7 billion trees by the end of next year. You can go here for more information.