DEFORESTATION: cutting down and removal of trees (CAUSES (Growth of…
DEFORESTATION: cutting down and removal of trees
Tropical rainforests have high biodiversity and is home to a high number of endemic species. In addition, grasslands and savanna are home to many other types of vegetation and serves as a natural habitat for a large number of diverse wildlife. The accelerated destruction of the rainforest is what has caused a concern.
Growth of Settlements
Large-scale land clearance was carried out in second half of the 1900s to settle migrant farmers.
Happen under government planning and from spontaneous migration of poor and landless people
Other demands and developmental policies such as highway construction to improve accessibility are also destroying forest in various countries such as in Brazil where they carried out the Trans Amazonian Highway deforestation.
Growth of agriculture
This also done as part of shifting cultivation, referring to plots of land being cultivated temporarily, before being abandoned and left to revert back to its natural vegetation while farmer moves to another plot.
After tree clearance, land exposed to heavy rainfall that can cause soil erosion. After a year or so, farm plot abandoned and farmer moves on to clear another rainforest. Abandoned plot may take 100 years to recover due to soil structure being destroyed
Slash and burn agriculture by landless peasants > led to cutting down of trees and burning them to release nutrients. However these nutrients are available for only one or two seasons.
Agriculture usually carried out. by small-scale farmers who grow many types of crops. FOR EXAMPLE: In Indonesia where many small farmers grow rice. Other types of crops grown in tropical regions include sweet potatoes and bananas
Increasing debate on extent to which agriculture is the chief cause of deforestation. There have been debates that recent studies show that small-scale farmers and shifting cultivation do not cause majority of the deforestation
Growth of Industries
Tropical light hardwood trees in high demand for industrial purposes
However, when tall trees are felled, smaller trees brought down since they are attached to each other by creepers such as lianas.
Thus large areas of trees cleared when trees are cut down
Logging can also lead to clearance of forest to create roads for access
Trees also logged for firewood, which is destructive for drier forests in the tropics. Especially so in many parts of Africa where firewood collection and wood fuel for charcoal serves as income to small farmers
Mining of materials like gold, silver and copper can lead to deforestation > before minerals from under ground are extracted, vegetation needs to be cleared to expose the ground. Then machinery used to dig up the minerals from the ground.
EXAMPLE: Mining of Iron ore in Carajas, Brazil, has led to the massive clearance of forest and building of roads for transportation.
Also a rise in plantation agriculture to produce larger amount of crops for exports to meet global demand
FOR EXAMPLE: Rainforests have been cleared in Malaysia and Indonesia for oil palm plantations. About 3.5 million hectares of forest was lost due to the large-scale oil palm expansion between 1990 and 2010.
In some areas, landowners clear large areas of land to be used for cattle ranching, responding to the high demand for beef from DC
Palm oil is used for wide variety of products. They are used in everyday products as well, such as cosmetics, food and detergent.
ACTIONS HUMANS CAN TAKE TO MANAGE TROPICAL DEFORESTATION
Selective (Best measure)
Refers to selective cutting down of trees that loggers choose to cut down trees with wood that are highly valued while leaving others intact.
This is done so instead of clear-cutting, which refers to the indiscriminate cutting down of trees and clearing of forests.
Helps to preserve the biodiversity of the rainforest and does not lead to destruction of animal habitat. Can also minimise soil erosion.
However, downside is due to the presence of creepers such as lianas, which twine itself around multiple trees, the cutting down of one tree can also lead to the toppling of other trees.
At the same, it is difficult to monitor logging and detect illegal logging activities. Thus due to the difficulty in enforcement, it may not be fully effective.
Planning and maintaining forested areas for the benefit and sustainability of future generations by authorities or other stakeholders.
Forests are identified and protected against deforestation. Usually works together with other methods of forest management.
FOR EXAMPLE: Reducing Emissions of Deforestation and forest Degradation: A vehicle to encourage developing countries to reduce emissions and enhance removals of greenhouse gases through a variety of forest management options.
serves as a more sustainable use of land, where ecological functions of trees animals and crops have the potential of increasing food production while simultaneously reducing agriculture's footprint on the environment
trees provide resources such as food and fuel wood. At the same time, it acts as protective function such as wind breaks, soil conservation and soil improvement
However, it may not be affective when theres competition for growth between plants, leading to lower productivity. At the same time, tree-crop interactions that can make agroforestry systems very productive can also make them unpredictable in other locations.
EXAMPLE: Laucena, a tree that was productively grown in Central America, was planted in Ethiopia, it completely failed to grow.
This is especially so when trees and crops have shallow roots, which leads them to compete for water and nutrients,hence the lower productivity.