Here's our situation in a nutshell!
One: we are what physicists call, dissipating systems. We need to take matter and energy from our environment in order to live. But it can't just be any matter-energy; it has to be low entropy (useful) matter-energy. This matter-energy goes through our system, fuels and maintains our bodies, and ultimately returns to the environment as waste. If we stop the throughput of the matter-energy to our systems we soon reach equilibrium.
- Our economy is much the same. It takes low entropy matter-energy (natural resources), which it uses as throughput to manufacture goods and create services and finally, high entropy (far less useful) wastes result. If throughput to the economy stops, the economy stops.
- In both of the above instances, the low entropy matter-energy that is required comes from ecosystems and the biodiversity they contain. Not only do ecosystems provide the direct, useful matter-energy in the form of resources, but through what ecologists call "ecosystem services," they provide other life support services, such as clean air and water on a global scale, pollination of many plants, including many of our food crops, buffers from storm and drought events, and scores of others, that allow both the organism (including us) and the economy to continue its existence. It is the collective actions of the myriad organisms within a particular ecosystem—its biodiversity—that allows the ecosystem to function.
- Ecosystems are finite, which means that the amount of matter-energy that's available for humans and the human economy is finite, with the exception of solar energy. But our demand for a constantly growing economy means we take more and ever-more resources from the ecosystems for throughput to the economy, an impossible goal on a planet with finite resources. This growth invariably results in degraded ecosystems, lost biodiversity, and even the liquidation of the ecosystems themselves. If we continue to exceed the carrying capacity of the biosphere by consuming resources in an unsustainable manner, eventually we will reduce ecosystems to the point where they will collapse. This means that the life-support systems of the biosphere will collapse. And this means ... well, you know what this means!
- It's important to understand that in order to use the resources in a sustainable way we not only need to reduce the throughput of resources to the economy but we must also leave enough of the natural ecosystems and biodiversity to allow proper ecosystem functioning so the provision of the life-supporting ecosystem services is maintained. This means we have to keep the level of economic throughput sufficiently below the physical and ecological limits of the biosphere in order to maintain an adequate amount of ecosystems and biodiversity.
- Based on the best science we have to date, we have already exceeded the carrying capacity of the planet.1 That is, we're using nature's capital at a rate that far exceeds the regenerative rate of the renewable resource and we're dumping our wastes at a much faster rate than the biosphere can assimilate them. We're also using non-renewable resources at a much faster rate than we can generate substitutes for. Simply put, our current lifestyles are not sustainable. Sounds serious, to us.
- If we want to be sustainable, it's time to choose another way—a sustainable way— that allows us to live on the Earth without harming the life support systems of the biosphere. However, we don't have much time. As the Board of the Millennium Ecosystem Assessment recently noted, “the ability of the planet’s ecosystems to sustain future generations can no longer be taken for granted.”2
1 World Wide Fund for Nature. 2006. The Living Planet Report 2006. (Accessed 10 November 2007). Note: this link opens a new window.
2 Millennium Ecosystem Assessment. 2005. Living beyond our means: natural assets and human well-being. Statement from the board. Island Press, Washington, D.C. 28 pp. " (Accessed 23 November 2007). Note: this link opens a new window.