Deforestation is the conversion of forested areas to non-forest land for use such as arable land, pasture, urban use, logged area, or wasteland. Generally, the removal or destruction of significant areas of forest cover has resulted in a degraded environment with reduced biodiversity. In many countries, massive deforestation is ongoing and is shaping climate and geography.
Deforestation results from removal of trees without sufficient reforestation, and results in declines in habitat and biodiversity, wood for fuel and industrial use, and quality of life.
Since about the mid-1800s the Earth has experienced an unprecedented rate of change of destruction of forests worldwide. Forests in Europe are adversely affected by acid rain and very large areas of Siberia have been harvested since the collapse of the Soviet Union. In the last two decades, Afghanistan has lost over 70% of its forests throughout the country. However, it is in the world's great tropical rainforests where the destruction is most pronounced at the current time and where wholesale felling is having an adverse effect on biodiversity and contributing to the ongoing Holocene mass extinction.
About half of the mature tropical forests, between 750 to 800 million hectares of the original 1.5 to 1.6 billion hectares that once covered the planet have fallen. The forest loss is already acute in Southeast Asia, the second of the world's great biodiversity hot spots. Much of what remains is in the Amazon basin, where the Amazon Rainforest covered more than 600 million hectares. The forests are being destroyed at an accelerating pace tracking the rapid pace of human population growth. Unless significant measures are taken on a world-wide basis to preserve them, by 2030 there will only be ten percent remaining with another ten percent in a degraded condition. 80 percent will have been lost and with them the irreversible loss of hundreds of thousands of species.
Many tropical countries, including Indonesia, Thailand, Malaysia, Bangladesh, China, Sri Lanka, Laos, Nigeria, Liberia, Guinea, Ghana and the Cote d'lvoire have lost large areas of their rainforest. 90% of the forests of the Philippine archipelago have been cut. In 1960 Central America still had 4/5 of its original forest; now it is left with only 2/5 of it. Madagascar has lost 95% of its rainforests. Atlantic coast of Brazil has lost 90-95% of its Mata Atlântica rainforest. Half of the Brazilian state of Rondonia's 24.3 million hectares have been destroyed or severely degraded in recent years. As of 2007, less than 1% of Haiti's forests remain, causing many to call Haiti a Caribbean desert. Between 1990 and 2005, Nigeria lost a staggering 79% of its old-growth forests. Several countries, notably the Philippines, Thailand and India have declared their deforestation a national emergency.
