People cut
down 15
billion trees every year. Forests cover 30% of the world’s land
area. In the United States, 30% of previously-forested areas have
already gone. Most of it occurred during a logging boom that started in
1880. By 1920, more than two-thirds of U.S. forests had been leveled
at least once.
In the
East, 99% of old-growth forests have
either been cleared for farming or housing or replaced by second-growth
forests. In the Midwest, oak savannas have been reduced to small areas
surrounded by corn fields. In the Pacific Northwest, diverse, ancient forests
have been replaced with a monoculture of young trees regularly harvested.
Deforestation
has four causes. The most critical is agriculture. In developing countries,
small farmers use slash and burn agriculture.
They cut down trees and then burn them.
The second
biggest cause is logging operations. Illegal logging is responsible for
between 15% and 30% of all wood traded globally. It's estimated to be worth
between $30 billion and $100 billion annually. Interpol estimates that
illegal logging is responsible for:
- Between
50% and 90% of deforestation in the Amazon Basin, Central Africa, and
Southeast Asia.
- From 40%
to 60% of timber production in Indonesia.
- One-fourth
of Russia's timber exports.
Development is
the third cause of deforestation. In the United States, 33% of all houses
are near a forest.
The fourth
cause is wildfires. Since 1970,
wildfires in the western United States have increased by 400%. They have burnt
six times the land area as before. In 2017, U.S. wildfires burnt 9.1 million acres of
forests. Recent wildfire intensity and frequency are worse now than in the
past 10,000 years.
Deforestation costs $4.5 trillion each
year through the loss of biodiversity. For example, half of all pharmaceuticals
comes from genetic resources.
Deforestation
has eliminated habitat for millions of species. In fact, 80% of Earth’s
land animals and plants live
in forests.
Long-term, it
worsens climate
change. The tree canopy keeps the forest soils moist and more resistant to
wildfires, droughts, and
subsequent floods. The canopy
also blocks the sun’s rays during the day and holds in heat at night.
Without it, the environment gets hotter during the day.
Trees
perpetuate the water
cycle. They return water vapor to the atmosphere and help increase
rainfall.
Trees also
absorb carbon dioxide, one of the greenhouse
gases that cause global
warming. Deforestation adds 15% of the CO2 in the
atmosphere, more than the carbon from all cars and trucks. Between 2000 and
2009, 32 million acres of tropical rainforestwere cut down.
At that rate, deforestation will add 200 billion tons of carbon into the
atmosphere in coming decades.
In the last 50
years, 17% of the Amazon rainforest has been destroyed. It might not seem like
much, but the tipping point is 20%. At that
point, the rainforest's water cycle won't be able to support all the ecosystems
within it. The eastern, southern, and central Amazon region would become a
savannah. The Amazon generates half of its own rainfall. It recycles
moisture from the Atlantic at least five times before it reaches the Pacific.
The trees absorb rainfall, then release it through transpiration from their
leaves. The moisture ascends into clouds that shed more rain. The water cycle
keeps the air humid and rainfall constant. Deforestation disturbs the
stabilizing effects of the Amazon's water cycle. The result is intermittent
droughts and floods. The Amazon
region had severe droughts in 2005, 2010 and
2015-2016. It had severe floods in 2009, 2012, and 2014. Scientists believe
these were the first signs of destabilization.
At current
rates of deforestation, the world’s rain forests will be gone by
2120. Unless, globally we learn to pay nations to keep their forests. That
amount must equal the potential economic benefits of alternative land use.
References:
1.
Deforestation Facts, Causes, Effects, and
What You Can Do, Kimberly
Amadeo, The Balance (https://www.thebalance.com)
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