We are used to thinking of deforestation as a cause of global warming and environmental disaster. While most of us understand, in a vague way, that the destruction of the Amazon rain forest is bad, we may not understand the full effects of deforestation, in the Amazon and other areas. For many people, it’s something we know a little about, but have not given a lot of thought.
It’s important to understand the damage deforestation causes. While your individual actions can’t stop deforestation, those actions and your understanding of the problem can contribute to a global solution.
Deforestation is the permanent removal of trees from very large areas of land. Degradation is the damage inflicted underneath the canopy without actual removal all trees. There are many different types of forests but when we refer to deforestation, we’re usually talking about the Amazon rain forests, where loss of trees causes the most environmental damage, but any large-scale removal of trees is known as deforestation.
Deforestation does not always happen in one large block of ground, but as a gradual incursion into and fragmentation of the forest. This destruction has many very serious side effects.
Tropical forests of all varieties are disappearing rapidly as humans clear the natural landscape to make room for farms and pastures, to harvest timber for construction and fuel, and to build roads and urban areas. Once roads are developed it creates access to areas that previously could not be penetrated. This leads to more deforestation.
Although deforestation meets some human needs, it also has profound, sometimes devastating, consequences, including social conflict, extinction of plants and animals, and climate change—challenges that aren’t just local, but global.
Many endangered species of plants and animals live in the rain forests, and destruction of their habitats threatens biodiversity and may lead to their extinction. We do not and cannot know what these extinctions will mean for the world, but they could possibly deprive us of medicinal plants that could greatly benefit many people.
Global markets consume rainforest products that depend on sustainable harvesting: latex, cork, fruit, nuts, timber, fibers, spices, natural oils and resins, and medicines. In addition, the genetic diversity of tropical forests is basically the deepest end of the planetary gene pool. Hidden in the genes of plants, animals, fungi, and bacteria that have not even been discovered yet may be cures for cancer and other diseases or the key to improving the yield and nutritional quality of foods—which the U.N. Food and Agriculture Organization says will be crucial for feeding the nearly ten billion people the Earth will likely need to support in coming decades. Finally, genetic diversity in the planetary gene pool is crucial for the resilience of all life on Earth to rare but catastrophic environmental events, such as meteor impacts or massive, sustained volcanism.
When the forests are destroyed, the roots that once held soil in place are gone, and soil erodes quickly, which can cause silting of rivers and dams, among other problems. Soil erosion is a natural process but accelerates with deforestation. Trees and plants act as a natural barrier to slow water as it runs off the land. Roots bind the soil and prevent it from washing away. When the sediments deposit in the rivers, they can clog dams and reduce the flow of the rivers. The absence of vegetation also causes the topsoil to erode more quickly. It’s difficult for plants to grow in the less nutritious soil that remains. No trees to stop water also means more frequent floods, as the water is not absorbed by the roots. And the erosion and rapidly moving water can lead to landslides, which can damage homes, destroy crops and threaten human safety.
Once the forests have been cleared several times, the land will no longer grow trees, and has become desert. This is called, suitably enough, desertification. The watersheds are also degraded, reducing the amount of water available for lowland communities. And coral reefs in the ocean are ruined due to the flooding and siltation.
As you may have noticed, none of this even includes the greenhouse effect and global warming. Deforestation increases the amount of carbon dioxide in the air, and threatens the ozone, resulting in global warming. This in itself is a very serious threat to the environment and the climate, but as you see, it is only one of the many threats posed by deforestation.
It is sometimes difficult to feel very concerned about something you don’t understand well or feel direct impact from. The more you know about deforestation, the more concerned you’ll likely become.