Sunday, September 15, 2013

Environmental Issues: Deforestation

There are numerous environmental issues currently plaguing our planet and threatening the function of our ecosystems and the species they contain, which in turn threatens our own survival and quality of life.  Among these issues are pollution, deforestation, climate change and others.  In these “Environmental Issues” articles, I’ll take a closer look at each of these threats and investigate how they specifically affect Washington State.

When it comes to environmental issues today, deforestation is one of the “big ones”, and affects every part of our ecosystems: air, soil, water, and the species that live there.  According to the World Wildlife Fund, forests currently cover 31% of the planet, and are being lost at a rate of 46-58 million square miles per year due to logging, development, or conversion of forestland to agriculture. This is roughly equivalent to losing a forest area the size of 36 football fields per minute.  When we think of how important forests are to our planet, that rate of forest loss is frightening to consider!

Our forests are not just pretty to look at-- they also provide essential ecosystem functions:

Carbon sequestration: forests are “sinks” for carbon, meaning that trees and other forest vegetation store carbon in their tissues and prevent it from being released into the atmosphere. Deforestation is responsible for an estimated 15% of global greenhouse gas emissions per year

Clean air: trees and other vegetation take in carbon dioxide from the air and turn it into oxygen.  I think we’ve all experienced that wonderful moment when you walk into a forest and take a great deep breath of air so fresh that it’s nearly intoxicating.  We can thank the trees for that!

Clean water: forests help to keep waterways clean by holding soil in place and preventing it from washing into streams and rivers.  Additionally, trees can take up contaminants from water and soil, preventing them from contaminating our water sources.

Habitat: forests provide habitats for innumerable species of animals.  The biodiversity of tropical rainforests alone is astounding: an estimated 80% of known and documented species can be found in these forests.

Deforestation is the gravest threat in areas of the world containing tropical rainforests.  In the Amazon and areas of Indonesia especially, rainforest is being plowed over or burned for conversion to agriculture, cattle ranches or palm oil plantations at alarming rates.  Already, 20% of the forest cover in the Amazon has been lost, and along with it, the environmental stability and biodiversity of those areas.  Deforestation is a major problem in many parts of the world, but I always wonder…

What about Washington?
Is the Evergreen State suffering such alarming deforestation rates as other parts of the globe? A US Forest Service report for the years 2002-2006 indicated that Washington State is actually faring pretty well at the moment. Today, the forest cover in Washington is at about 50% of total land area, and is being converted to other uses (agriculture, development, etc.) at a rate of around 0.37% per year. Despite the slowly declining forest cover, Washington forests are currently a net sink for carbon. This means that tree growth in our state exceeds the rate of tree harvest and mortality, so our forests are actually helping to curtail greenhouse gas emissions rather than contributing to them.

The horizontal notch in this cedar stump at St. Edward State park in Kenmore is evidence 
of the logging that occurred here earlier in the 20th century.  Loggers inserted a springboard 
into this notch to stand upon as they chopped the tree down.

My research turned up two major causes of deforestation in our state: Our well-established timber industry and a growing population resulting in conversion of land from forest to subdivisions and developments.

It is common knowledge that Washington has had a healthy timber industry since being settled over a hundred years ago—in fact, much of the forested land that surrounds us is actually second growth forest that thankfully returned after the area was logged decades ago.  For the most part, the timber industry in our area manages their forestland well by replanting trees and selectively logging different areas, so to avoid clearcutting large swaths of land all at once.  These sustainable forestry practices protect our natural resources and ensure that tree harvest rates do not exceed the forest’s ability to regenerate. Drive through the Weyerhaeuser logging areas in southwest Washington and you’ll be able to see new forests in varying stages of maturity after the land was logged and replanted years ago.

Although the timber industry in our state seems to be doing well overall with sustainability, the land development side of things has unfortunately not kept pace.  A Department of Natural Resources report notes that with the population of our state expected to increase significantly over the next few decades, increasingly more forestland will be developed to sustain the influx of people. New subdivisions with paved streets and non-native landscaping are replacing forests at alarming rates in some areas. These subdivisions create costly problems with pollution and increased stormwater runoff, which the forests once used to mitigate. In our state, deforestation due to conversion of land to subdivisions is expected to have the highest rates in the Puget Sound area and along the I-5 corridor.

New housing in the Issaquah highlands.  

With a growing population and increasing rates of deforestation, what are some of the threats that are a particular concern in Washington?

We love our salmon here in Washington . Along with apples and evergreen trees, they are among our state’s most well-known natural resources. However, it would not be possible to have salmon without the forests which are so critical to maintaining ideal salmon habitat.  They shade the rivers and streams and prevent water temperatures from becoming unsuitably warm.  Trees also help to hold soil in place along stream and river banks, controlling erosion and keeping the water clear and clean.

Wildlife such as bears, cougar, deer, owls and others are being displaced as their forest habitats are cut down and converted into other uses.  These days, stories of bears or coyotes wandering through someone's backyard are considered newsworthy.  However, human-wildlife encounters should only be expected to increase as humans continue to build their homes in the formerly forested areas where these animals once lived.

Polluted Rainwater Runoff
In our rain-drenched climate, rainwater runoff can become a serious problem in areas that have been subjected to deforestation.  When an area is logged, leveled, paved over and crammed with new homes, the trees that once took up the rainwater are no longer there.  As a result, there is no place for the rainwater to go except to wash down streets and into storm drains, where it is then funneled into nearby waterways.  This can lead to pollution of creeks and rivers, as the runoff contains oil, heavy metals, and other pollutants picked up along the way. 

Landslides and Erosion
Without tree roots to anchor the soil, hillsides and riverbanks will become unstable.  We’ve already seen news stories about homes in danger of sliding off the edge of a hill after heavy rains instigated massive landslides.  

Loss of Identity
What a sad day it would be if we ever get to the point where Washington is no longer known as the Evergreen State.  I truly hope that we do not ever see the day where we have removed so much of our forest land that our very identity is altered.  A Washington with barren hillsides covered in rows of cookie-cutter houses, muddy waterways bereft of salmon, and skylines comprised solely of buildings instead of treetops is not Washington to me. Thankfully, a portion of our forests are either under state or federal protection, and will not be in danger of deforestation.  When it comes to private landowners, the Forests and Fish Law provides  management practices to ensure that activities on privately owned lands are protecting salmon habitat and clean water.

It is encouraging to see that deforestation, as of right now, is not an out-of-control problem in Washington State.  Yes, forest cover is decreasing each year as land is converted from forest to other uses, but there are protections in place to help keep potential deforestation threats from getting out of hand.  And let’s not dismiss the potential of millions of Washingtonians who are passionate about their Evergreen State and want to keep it that way!  Together, we can have a very formidable and powerful voice to ensure that our forests do not disappear.

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