Deforestation
Deforestation is clearing Earth’s forests on a massive scale, often resulting in damage to the quality of the land. Forests still cover about 30 percent of the world’s land area, but swaths the size of Panama are lost each and every year. The world’s rain forests could completely vanish in 100 years at the current rate.
Forests are cut down for many reasons, but most of them are related to money or to people’s need to provide for their families.The biggest driver of deforestation is agriculture. Farmers cut forests to provide more room for planting crops or grazing livestock. Often many small farmers will each clear a few acres to feed their families by cutting down trees and burning them in a process known as “slash and burn†agriculture.
Logging operations, which provide the world’s wood and paper products, also cut countless trees each year. Loggers, some of them acting illegally, also build roads to access more and more remote forests—which leads to further deforestation. Forests are also cut as a result of growing urban sprawl.
Not all deforestation is intentional. Some is caused by a combination of human and natural factors like wildfires and subsequent overgrazing, which may prevent the growth of young trees.
Deforestation has many negative effects on the environment. The most dramatic impact is a loss of habitat for millions of species. Seventy percent of Earth’s land animals and plants live in forests, and many cannot survive the deforestation that destroys their homes.
Deforestation also drives climate change. Forest soils are moist, but without protection from sun-blocking tree cover they quickly dry out. Trees also help perpetuate the water cycle by returning water vapor back into the atmosphere. Without trees to fill these roles, many former forest lands can quickly become barren deserts.
Removing trees deprives the forest of portions of its canopy, which blocks the sun’s rays during the day and holds in heat at night. This disruption leads to more extreme temperatures swings that can be harmful to plants and animals.
Trees also play a critical role in absorbing the greenhouse gases that fuel global warming. Fewer forests means larger amounts of greenhouse gases entering the atmosphere—and increased speed and severity of global warming.
The quickest solution to deforestation would be to simply stop cutting down trees. Though deforestation rates have slowed a bit in recent years, financial realities make this unlikely to occur.
A more workable solution is to carefully manage forest resources by eliminating clear-cutting to make sure that forest environments remain intact. The cutting that does occur should be balanced by the planting of enough young trees to replace the older ones felled in any given forest. The number of new tree plantations is growing each year, but their total still equals a tiny fraction of the Earth’s forested land.
The systematic and continued removal of trees and bushes from an area of land.
Deforestation is the change of a forest to some other type of land by cutting the trees and other plants. One possible motivation is to use the trees for building materials or for fuel. Alternatively, the cleared land can be used for agriculture or human settlements.
It is believed that deforestation, resulting from mainly human activity, has occurred for at least 40,000 years, although it can also have natural causes such as fires. The amount of deforestation has been accelerating with human population growth. It has spread to most regions of the world particularly since the industrial revolution.
Deforestation is a contributor to anthropogenic climate change.
Because forests have lower albedo than most other types of land, deforestation can lead to local and short term cooling. The long term effect of deforestation is more likely one of global warming because forests function as carbon sinks. When forests are removed and the wood is burned extra CO2 is released in the atmosphere. Furthermore, the lack of tree and plant growth means that less carbon will be removed from the atmosphere through photosynthesis.
It is estimated that tropical deforestation alone is responsible for about 20 percent of global greenhouse gas emissions. The IPCC further notes that deforestation on a global level contributes almost a third of the anthropogenic greenhouse gas release.
Deforestation also reduces the amount of carbon that can be stored in soil, and it results directly in a decline in biodiversity because habitat is destroyed.
Like the rest of the world, the Pacific region is experiencing rapid deforestation and its related problems. Research has confirmed the global importance of forests and the need to preserve them.
It has been estimated that the original area covered by forests was about 6 billion hectares. According to a report published by the Intergovernmental Panel on Climate Change (IPCC), the total area presently covered by forests amounts to some 4 billion hectares. Half of this is accounted for by the tropical forests, one-third is covered by northern forests, and about one-sixth represents temperate forests. The total amount of carbon stored in these forests is equal to that presently contained in the atmosphere, i.e., about 700 billion tons.
Clearing and burning of forests can cause irreparable damage to the soil, environment, and can affect the climate. Deforestation increases the atmospheric carbon dioxide by removing the source of carbon dioxide uptake. Commercial logging, establishment of new agricultural plantations, shifting agriculture, cyclones, fire, land and road developments, all contribute to deforestation. Forests are important not only for their role in maintaining biological diversity, but also because of their role in global climate. The forests absorb carbon dioxide carbon dioxide generated by human activities. The present massive destruction of tropical forests at a rate of 17 million hectares per year (11.3 million in 1980) could lead to a greater buildup of carbon dioxide in the atmosphere. This would contribute to the global warming effect.
Deforestation also affects the soil and local climate. It reduces the evaporative cooling that takes place both from soil and from plant life. This can result in increased soil erosion and runoff of rainfall, flooding, and sedimentation of rivers, lagoons, and reefs. In fact, the total ambient near surface humidity is drastically modified. Rainfall is no longer intercepted by the forest foliage to be recirculated to the atmosphere, but falls immediately to the ground to be transported, perhaps directly, to the ocean in runoff or else rapidly made inaccessible in the short term by it being contributed to the underground water table. Moreover, there are no longer the deep roots of the former forest trees to return it by transpiration to the atmosphere. Again the landscape is changed, usually permanently. The albedo, or reflective capacity of the surface, is greatly increased with all that such a change can be inferred for the local climate. Uncontrolled and poorly managed clearing of forests can have devastating effects on the climate, both regionally and globally.
15-29
2013
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