Wednesday, October 14, 2009

IS THIS EVEN A QUESTION?

Question: Many scientists consider humans as the most invasive species, as humans can greatly change an environment and impact living things that reside there. Are we being stewards of the world? Take a look at an issues in which human intervention has positively or negatively affected the biodiversity of our ecosystems.

















Our world is evolving... No doubt about that. But, can we really, truthfully, sincerely tell someone that being a steward of the world is one of our main priorities in life. These days, many people are so caught up with their dilemmas and duties, that they are not attentive to how they are treating their home. That's our problem right there. Many people would ONLY describe their home as being the place in which their family resides at, when really, the whole world is our home (yeah, a tad corny, but nonetheless very accurate). It's obvious that many of us would not litter inside our house, who would? Maybe only those who aren't scared of a raging mother lecturing us on how different her life was as a child, and how hard her duties and consequences were. So, for all those good kids who do listen to their mothers (hats off to you!) we instead take the time to get up off our butts (very rare occasion, indeed) and actually throw our garbage into the trash can.

Humans are the smartest mammal on the Earth. Correct? So, should we not realize that the car that we choose to go into, for that ten minute ride to school, is polluting our atmosphere? Or that the litter that we carelessly throw onto the road, is dirtying our Earth? Or that the computer that we leave on, all day is causing the burning of fossil fuels? It seems that everything that we do in our daily routine, somehow always has a negative effect on the world.

One of the most major environmental problems is global warming. Our Earth was once protected by a once secure and strong ozone layer. The ozone layer protects humans from the sun's harmful rays, such as the ultraviolet rays (UV-B). Through the years, scientists found that certain man-made products damaged the ozone layers, making us more vulnerable to the sun's rays. Scientists have found that the production and use of chemicals like chlorofluorocarbons (CFCs) in aerosol sprays, refrigeration, insulation and air conditioning was contributing to the accumulation of ozone-depleting substances (ODS) in the atmosphere.

















The damage to the ozone layer does have a impact on the human population. The thinning of the atmosphere increases the chances of skin cancer and also cataract in the eye, children being especially vulnerable. Personally, I love being outside in the sun. I could spend countless hours with the sun's rays beaming down on my face. The fact that harmful ultraviolet rays are becoming more and more of a hazard, concerns me. I would never wish upon skin cancer, or any other sickness, due to the amount of time I spend outside under the sun.

Increased UV-B rays impacts biodiversity since it reduces levels of plankton in the oceans and subsequently diminishes fish stocks. It also impacts plant growth, resulting in decreased agricultural productivity, effecting herbivores, which will affect omnivores and the chain continues.

We can see how global warming has had an effect on our world, by looking at the polar bear population. The polar bear, or also known as the Ursus Maritimus, is native to the Artic Circle. Polar bears can also be found residing in Alaska, Russia, Norway and Greenland. Approximately sixty percent of the species population can be found in Canada. Polar bears have a life span of around twenty to twenty-five years. The species spend their time in ice cold water, or on sea ice. The sea ice is used by the polar bears as a hunting platform to catch marine mammal prey. Without the presense of sea ice, they have difficulty meeting their dietary needs.

Due to global warming, temperatures in the atmosphere are continuously increasing. The temperature in the Artic Circle is rising twice as fast than the rest of the world. Since 1978, sea ice cover has declined by approximately nine per cent per decade, and the rate of melting appears seems to be on the rise, as years go by. Studies have been shown that with the ice melting quickly in the Artic Circle, the polar bears are being robbed of the ices floes. This resusts in the polar bears being forced ashore. This increased amount of time on land leads to weight loss, physical deterioration and decreased rates of reproduction. It is predicted that by 2012, the polar bear population in the Western Hudson Bay, will by unable to reproduce.

Can you imagine this? The whole polar bear population being wiped from the face of the Earth? Does that not strike a signal in your mind that the human poulation have done much damage? IF things do not start chnaging, it won't be soon until many other animal populations become endangered. Change needs to happen, and it needs to happen quickly.

WORKS CITED
http://www.davidsuzuki.org/Conservation/Endangered_Species/Canada/polar_bear_facts.asp?gclid=CPvhjL6gzp0CFZho5QodVB24yg#

http://www.worldviewofglobalwarming.org/

http://globalwarming.com/

http://www.naturecanada.ca/advocate/polar_bears.html?gclid=CMz1gdanzp0CFcZM5QodL01HsQ