More than 13 per cent of Canada's gross domestic product depends on healthy ecosystems, according to Environment Canada briefing notes obtained by Postmedia News. By contrast, the Harper government's pet economic project, the Alberta oil sands, represents a mere 2 per cent. But is 13 per cent a reasonable estimate of the "value" of nature? With the current perspective that elevates the economy above all else, it's important to find ways to include nature's value in our calculations so it doesn't get ignored in decision-making. At the same time, it seems absurd to try to assign worth to something so vital we can't survive without it.
Most of the world's people are now urban dwellers and spend increasingly less time outdoors. As such, we assume we can create our habitat. As long as we have parks to play in, we don't think much about nature. So, let's consider a thought exercise.
Scientists invent a time machine to take us back four-billion years before life appeared. We strap ourselves in, press buttons and are transported to a time when the planet was sterile, devoid of life. We open the hatch and go out. And, we're all dead! That's because before life arose, the atmosphere was toxic for animals like us -- rich in CO2, ammonia, sulphur and water, but devoid of oxygen.
Oxygen is a highly reactive element that is quickly used up when elements like sulphur and iron oxidize. Only after life evolved a way to exploit the sun's energy through photosynthesis was carbon dioxide removed and oxygen released as a byproduct. Over millions of years, photosynthesis liberated oxygen, which built up to become 20 per cent of the atmosphere. To this day, all green things on land and in oceans maintain the balance between oxygen and carbon dioxide.
However, since the Industrial Revolution, we've been burning fossil fuels, liberating more carbon dioxide than life can absorb. It's accumulating in the atmosphere and oceans, and that's driving climate change.
Back to our experiment. We knew about the toxic atmosphere before we started out and so we packed helmets and compressed air tanks, which we don before opening the hatch. We exit and wander about, looking at the eerie, barren landscape for an hour or two before becoming thirsty. There's water, but what could we trust to drink? Life is part of the hydrologic cycle that circulates water around the world in rivers, lakes, oceans and air. Soil organisms like fungi and bacteria, as well as plant roots, filter molecules from water to render it drinkable.
We knew that, too, and so we have water bottles attached to our helmets, connected by straw to our mouths. After many more hours, we become hungry. But before there was life on Earth there was no food for animals like us because everything we eat was once alive! We consume the carcasses of animals and plants and absorb their molecules to form every part of our bodies.
We also anticipated that and brought food. In fact, I expected to stay a while and brought seeds to grow greens. But where could I plant them? There would be dust, sand, clay and gravel, but no soil because it's formed by the accumulation of molecules from the remains of plants and animals.
Finally, the sun sets and although it's warm because of greenhouse gases, we decide to build a fire so we can sit around and exchange stories. Where could we find fuel to burn? Wood, peat, dung, coal, oil and gas all store the sun's energy as photosynthetic products that we burn to liberate fire. Before life, there was no fuel. Again, in anticipation we brought wood, kindling and paper and set them up for a fire. But fire requires oxygen, so nothing happens when we strike the match.
The point of this exercise is to illustrate that the very foundations of our lives -- air, water, photosynthesis, soil and food -- are made possible by the web of life that evolved on a once-sterile planet. Living organisms on land and in oceans -- including us -- create, cleanse and regenerate those vital elements. Who needs nature? We do. Without nature, we would not be here. How do we put an economic value on that?
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