Producing, Exchanging, and Distributing:

Experts generally agree that the majority of rainforest destruction is due to agriculture,  cattle ranching, and logging.

                                   

Agricultural destruction comes in several forms.  Slash & burn is one of the most common methods.  The vast majority of rainforests exist in very poor countries.  A basic human need in these countries is the production of food.  Population growth in these countries contributes greatly to the destruction of the forests.  The people living in the countryside are typically very poor and depend on crops raised by themselves for their food. In Bolivia the average annual income is $800 per year as compared to $27,000 per year for people in the United States.  Local area farmers chop down a relatively small area (typically a few acres).  The tree trunks are burned to clear the area so that crops can be planted.   Unfortunately soils found in rainforests are rather poor for farming and the soil becomes depleted within a few years.  In a tropical rainforest nearly all of the nutrients are found in the trees and plants not in the ground. It is estimated that less than 10% of the Amazonian soils are suitable for sustained conventional agriculture.  After the soil is depleted of its nutrients the farmers must move on and cut down more rainforest.  Fortunately this method of destruction allows for the rainforest to grow back relatively  quickly.  A potential danger though is the extinction of species, which only exist in one small area of the forest.  Another danger is the cleared and depleted land could be sold to cattle farmers.  If the abandoned farms are allowed to revert to rainforest it is estimated that forest regeneration would take about 50 years.   Another type of farming practiced in the rainforest is shade farming.  In this type of farming many of the original rainforest trees are left to provide shade for crops.

 These shade crops would include coffee and chocolate.  When these farms are abandoned it is possible for the rainforest to regenerate within 20 years.

 

                                   

Large commercial farming on the other hand is a much greater threat to the rainforest.  Companies can use huge tractors, chainsaws, and fires to clear large areas of the rainforest.   These farms use more modern and harmful methods in growing crops.  Pesticides are used on a huge scale.  Research indicates that this use of pesticides is much more harmful to the environment than low-tech farming.  The use of pesticides greatly reduces the forest chance for regeneration.  The use of pesticides and fertilizers on farms disrupts the balance of an ecosystem.  The pesticides that are intended to kill pests kill many other organisms as well.  Birds, bees, worms, and other beneficial insects are killed along with the pests.  The most common crop grown in these conditions are bananas.  Water ditches and underground pipes are necessary for irrigation.  This may not sound harmful however it can permanently disrupt the natural water flow in the area.  After a banana plantation or similar farm is abandoned it will take at least 50 years and possibly centuries for a rainforest to regenerate.             

 

 Cattle Ranching is and has been a giant factor in rainforest destruction.  Brazil has encouraged cattle ranching by selling large tracts of rainforest land for very little money. 

Large companies and wealthy individuals were able to buy up huge areas to set up ranches.  Cattle ranching runs into the same problems as farming in the rainforest.  Poor soil makes it difficult to grow grass for the cows to eat year after year.  The soil continues to get depleted and after less than six years the land becomes useless for cattle ranching. 

 

                                   

When this happens, like the farmers the cattle ranchers must move on and clear more rainforest for new ranches.  Because cattle ranches are very large and the cattle eat virtually everything they can reach this type of land use makes forest regeneration nearly impossible.  It is estimated that land used for cattle ranching will take more than 50 years for forests to regenerate.  In addition very large cattle ranches could take much longer because forests will only regenerate where they are bordered by existing healthy rainforests.  Cattle ranching is more harmful to the forest than farming because it takes a much larger area of ranch land to produce the same amount of food.

 

                                   

Logging is one of the greatest threats to rainforest.  Logging threatens the rainforests in many different but connected ways.  The cutting of trees for logging differs from the clearing of forests for local farming.  In farming the trees are burned after they are cut so their nutrients will return to the soil.  In a logging operation the trees are not burned  and so no nutrients are returned to the soil.  There are two main types of logging, clear cut and selective.  In clear-cut logging all the trees in an area are cut down and removed.  In selective logging only the few of the trees are cut.  Another problem that logging creates is that it clears areas for farming and ranching. 

Selective logging sounds much less harmful than clear-cutting but it still is very damaging to the rainforest.  It is estimated that to cut only 3% of the trees in an area 49% of the trees in that area are damaged.  Modern heavy machinery used to chop and haul away trees damage many trees on the way in and out of an area.  To add to this destruction many of the trees, are interconnected by large vines.  Cutting down one tree can cause many trees to fall.  Heavy machinery also damages the soil by over compaction and the destruction of nearby root systems.  The use of heavy machinery also requires a road system to be built.  Selective logging occurs when companies are only looking for a certain type of tree.  Mahogany is one of the tree types that are selectively logged.  Mahogany is a popular wood for furniture making, especially in the rich industrialized  countries.  Even with so much damage being done selective logging is still much less harmful than clear-cutting.  Trees that are damaged by selective logging can still give off seeds and offer shade for young trees.  Rainforests can regenerate in selectively logged area in less than 50 years.

                                   

Clear-cut logging is the most harmful type of logging.  No trees are left to supply seeds or shade for forest re-growth.  No trees are left for animals to live in or feed off of. 

                                   

Since the trees are hauled away no nutrients are returned to the soil.  In an area that has been clear-cut heavy equipment damages virtually everything in the area.  Bushes are destroyed and the ground is torn up by equipment.  This destruction leaves the area susceptible to floods and mudslides that further damaged the soil. Scientists do not know how long it will take for clear-cut areas to grow back.  It will take substantially longer than 50 years.   When and if these areas are ultimately used for farming or ranching after the logging the soil is in very poor shape.  Because the soil is in such poor condition farms and ranches fail in a relatively short time period. 

             

                                                                       

The following chart shows the estimated time it will take for rainforests to grow back after various activities.