Over half of the world’s forests have been destroyed in the last 10,000 or so years, the majority of this loss has occurred in the last 50 years, occurring simultaneously with a massive increase in the human population. The incredible scale of this loss has led to significant changes throughout many parts of the world, and in recent years these changes have been accelerating. These changes include: large scale extinction events, desertification, climatic changes, topsoil loss, flooding, famine, disease outbreaks, and insect ‘plagues’, among others.
Deforestation occurs primarily due to: agriculture, fuel use (firewood, charcoal, etc), timber, pasture for livestock animals, and expanding human settlements. And also, to a degree, due to large scale war, throughout history fire has often been used as a way to deprive enemy populations of necessary resources. These areas almost always inevitably end up as wastelands via the processes of soil erosion and desertification, if they aren’t reforested. Many of the areas of the world that were deforested thousands of years ago remain as severely degraded wastelands or deserts today.
Currently the world’s annual deforestation rate is estimated to be about 13.7 million hectares a year, that’s about the land area of Greece. Roughly half of this area gets reforested to a degree, though new growth forests don’t function in the same way, support the same biodiversity, nor do they provide the many benefits that old-growth forests do. In addition to these numbers, forests have been becoming more and more affected by climate change, with increasing drought, forest fires, increased and more powerful storms, diseases, and an explosion in insect numbers.