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Effects of Deforestation

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Effects of Deforestation

帖子admin » 周四 8月 25, 2016 7:56 pm

http://environment.nationalgeographic.c ... -overview/
Modern-Day Plague

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 a hundred years at the current rate of deforestation.

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.
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Re: Effects of Deforestation

帖子admin » 周四 8月 25, 2016 7:57 pm

https://prezi.com/fbnefzfwz-72/life-cycle-of-a-pencil/
LIFE CYCLE OF A GREY LEAD PENCIL
design by Dóri Sirály for Prezi

PENCIL MANUFACTURE
Pencil manufacturing is almost completely mechanised (run by machines-minimal people are involved in the process). grooves are cut into the wood and the graphite is glued in. A second slab of wood is added to the top to create a 'sandwich' and is then cut into separate pencils.
CONSUMER USE OF PENCILS
Consumers may drive to stores to buy pencils. The average pencil holds enough graphite to draw a line about 56 kilometers long, or to write roughly 45,000 words.

Cedar, graphite, water and pumice, metal paint and wax are used to manufacture a pencil with an eraser on top.
The metals are mined from the ground as well as the graphite and pumice.
The wood is harvested from a tree called the California Cedar so to obtain this material deforestation must occur.
The rubber is harvested from a trees which are typically found in Asian regions and take fourteen years to mature. The metals are melted down and made into blocks. Extreme heat need to be used to complete this process.
The paint is created from dyes and chemicals.
ENIRONMENTAL IMPACTS OF PENCIL MANUFACTURING
LEAST SERIOUS
MOST SERIOUS
Deforestation
Deforestation of the rubber and Cedar trees results in the carbon dioxide being released back into the environment and not being able to soak up anymore. Also animals that live in these trees and around the trees loose their habitat and may die from the deforestation.

Transportation
These trucks use fuel which contaminates the air with carbon monoxide, nitrogen oxides, and hydrocarbons. Speeding up the process of global warming
machine use and cleaning
Pencils are mostly made from robotics and machines. This means that they need to be cleaned with water heated to extreme heat and chemicals to maintain use of the machine. The chemicals used are bad for the environment as well as water vapour which also quickens the process of global warming
Miss-use of pencil
pencils can be lost, mistreated and prematurely thrown out and the pencil is not used to its full potential and the whole process of manufacturing the pencil was a waste.
Mining
The ground is being ripped apart to get the desired materials(aluminium,pumice and clay powder). Habitats for both plants and animals are being ruined by huge machinery- which also uses a lot of fuel to power them releasing carbon monoxide, nitrogen oxides, and hydrocarbons into the air. Mining results in erosion, formation of sinkholes, loss of biodiversity, and contamination of soil, groundwater and surface water by chemicals from mining processes as well

Landfill
Many pencils are wrongly disposed of resulting in 1.6 billion disposable pens and pencils being thrown into landfill which can possibly end up in oceans- piling up and hurting the environment
e.g birds eating the pens and pencils and being stuck in their throat- suffocating the animal.
BIBLIOGRAPHY
http://www.coroflot.com/manuela_gaviria ... -n-layouts spanish life cycle
http://www.personal.psu.edu/users/a/y/a ... Pencil.htm pencil life cycle words
http://prezi.com/_k00-yvx_suj/pencil-lifecycle/ best prezi
http://prezi.com/fidcl-zg0pjw/pencil-lifecycle/ other prezi
http://www.worldwatch.org/node/6422 website
http://www.madehow.com/Volume-1/Pencil.html
EVALUATE THE BALANCE OF POSITIVE AND NEGATIVE CONSEQUENCES OF THE PROJECT
While the product does have negative impacts such as deforestation and mining there are also positive technology that is having a positive effect on the environment such as the BioPencil and rehabilitation of forests. If this product is properly recycled it can be used again which results in less negative effects. Companies are also now trying new strategies of how to make the pencil better for the environment with less waste.
Overall the production of pencils does have many negative impacts on the environment but up and coming companies with new, cleaner and more sustainable companies will surely make a 100% recyclable pencil in the future.
RANKED ENVIRONMENTAL IMPACTS
Deforestation of rubber and California Cedar trees.
COLLECTION OF MATERIALS
Mining of metals, pumice, clay powder, aluminium and graphite.
MANUFACTURING PROCESS
The lead in the pencil is made by mixing the graphite with clay. The California Cedar wood is dried, stained, and waxed, then sawed into narrow slats to the width of the pencil. The slats are dropped into a feeder and placed on a conveyor belt. The slats are given a flat surface and a semicircular groove along one of the slats. Half of the slats are given a coating of glue and the graphite is laid in the grooves of these slats. One unglued slat and a glued slat are pressed together and clamped. Once they are dried, the pencils are cleaned of glue. The pencils are then trimmed by cutters into a hexagonal shape so they do not roll off the belt. The pencils are then smoothed by sanders and coated in varnish and dried. The eraser is then attached using a metal case called a “ferrule”. The company logo is then pressed into the pencil by a heated steel die.

TRANSPORTATION
Trucks are used to transport the California Cedar and mined products such as graphite, pumice and other metals. These trucks use fuel which contaminates the air with carbon monoxide, nitrogen oxides, and hydrocarbons. Transportation is used many times throughout the process of pencil manufacturing.
BIO PENCIL
The company called Bio Pencil have been successfully been able to manufacture a pencil made to not harm the environment in any way.100% natural compound of farm-grown algae Its harmless to the environment in both its production and disposa.l Once the pencil has been used as much as possible the algae breaks down in the ground, but the company has also put plant seeds in the algae. The pencil can be simply planted in the ground; the algae will be a fertiliser for the grown plant. different seeds are available depending on region and plants in that area.



The wood goes to a mill where lumber is prepared. The preparing stage involves the wood to be cut as well as treated with chemicals to get rid of bugs and make the colour of the wood more prominent.
WOOD MILLS
Discarded pencils are donated to a nature centre where the wood and graphite can be recycled and reused. The metal may often be recycled as well but people will not pull apart the pencil and they are often thrown into the rubbish and off to land fill
DISPOSING OF THE PENCIL
Pumice, rubber tree
California cedar
Graphite, clay powder
Aluminium ferrel
pumice*
Main Difficulties
This SAC was challenging at first to find information on the life cycle of a grey lead pencil. Finding the flow chart proved difficult as the level of information I wanted on the diagram was quiet a lot. Most of the flow charts were very basic or did not include clear information. Finally finding the perfect flow chart but realising it was in a different language was very frustration. By that time I had wasted quite a lot of class and I decided to make my own with the information I had already found. After creating this flow chart, all the other tasks fell into place and the questions were easy to understand making this task much more enjoyable. Another problem I faced was finding the information within every stage of production. not all the information was on the one website so it took a while to find the specifics such as fuel pollution.
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