While we tend to think of protecting ecosystems for their aesthetic beauty and as the morally correct thing to do, there is growing evidence that ecosystem protection also makes a lot of practical and economic sense. This is because ecosystem functions like nutrient cycling, the water cycle, and interactions between species produce a whole range of goods and services that humans depend on for their very survival. The obvious examples are the production of wood in a forest, the production of food on a farm field, and the production of fish in the sea. But these products, while critically important, represent only a small fraction of the goods and services provided for us by natural systems. Other “services” of nature (or ecosystem services) include air and water purification, crop pollination, mitigation of droughts and floods, decomposition of wastes, and moderation of weather and climate. Without these tremendous free gifts provided to us by natural systems much of human life on this planet would cease to exist.
Yet, despite their critical importance, very few people are even aware of the concept of ecosystem functions and services. Because these services are “free,” and because we could always rely on them in the past, we have taken them for granted and overlooked their importance in our economic calculus of costs and benefits of development projects. A wetland is perceived to have little “value,” while the Wal-Mart or housing development that replaces it is said to generate tax revenue and create jobs. As a result we are ending up with more and more Wal-Marts and housing developments and less and less wetlands, forests and grasslands. The consequences for human society are not just aesthetic; the true economic costs of converting these ecosystems to other uses is beginning to become obvious in places like New York City, New Orleans, Florida and Pittsburgh. This segment of the class will examine the role of ecosystems in human wellbeing, the threats to these ecosystems, and what we might do to change the economic thinking that has resulted in their destruction. To use an analogy, thinking of a forest as only a source of timber is like thinking of Bentley Hall as only a source of bricks.
Start with a short 2-page introduction prepared by the Ecological Society of America entitled “What Are Ecosystem Services?” Next, read a more complete summary of what ecosystem services are, also prepared by the ESA and entitled “Ecosystem Services: Benefits Supplied to Human Societies by Natural Ecosystems.” Finally, read a short article on the practice of trying to estimate the economic value of some of the “free” goods and services provided to us by nature in “Aggregate Measures of Ecosystem Services: Can We Take the Pulse of Nature?”
The ESA series mentioned above includes another paper on the connection between biodiversity levels and the level of ecosystem services provided entitled “Biodiversity and Ecosystem Functioning: Maintaining Natural Life Support Processes.” This is an important issue because the loss of biodiversity does not just mean the loss of cute little critters but also the loss of services that we depend on for our wellbeing.
An article on the New York City program to conserve upstate watersheds in order to protect the city’s drinking water is called “How New York City Used an Ecosystem Services Strategy Carried out Through an Urban-Rural Partnership to Preserve the Pristine Quality of Its Drinking Water and Save Billions of Dollars.” (I know I know it’s a looooong title!).
A more general article on the role of ecosystems in protecting water quality was published by National Wildlife magazine and is entitled “How Much is Clean Water Worth?”
A very interesting, but controversial effort was made by some ecological economists a few years ago to measure the global annual value of ecosystem services provided to us. The article is entitled “The Value of the World’s Ecosystems and Natural Capital.”
Recently a mammoth report was prepared on the health of the world’s ecosystems called the Millennium Ecosystem Assessment. This project sought to document changes and trends in the world’s major ecosystems, and the impacts of these changes on human economies and health. If you are interested you can download a Power Point presentation summarizing the results of this research. If you’re really a glutton for punishment you can also read some of the reports coming out of this project. However, I would recommend the simple version of the project results at this page.