Tragedy of the Commons Any commons that is open to unregulated use will eventually be destroyed Destruction occurs because each person will be motivated to over-use the commons Because no one person owns the commons, no one has incentive to take care of it Everyone takes what he or she can until the resource is depleted

Columbia River Chinook (millions of kg) (from Beiningen, KT Oregon D.F. W.)

Environmental Economics Neoclassical Economics –Resources are infinite and substitutable –Long term effects are discounted –Costs and benefits are internal –Growth is Good Ecological Economics –Advocates sustainability and steady-state economies that mirror natural systems –

Supply and Demand

Sustainability The ability to supply with necessities or nourishment Global human needs will be met indefinitely Adequate FoodWaste Disposal Clean WaterInfrastructure Clean AirRecreation EducationGood Health

The Natural Step In a sustainable society, nature is NOT subject to systematically increasing –Concentrations of substances extracted from the earth’s crust –Concentrations of substances produced by society –Degradation by physical means In that society, human needs are met worldwide

Renewable vs. Non-Renewable Resources

Non-Sustainable

Sustainable