by Whit Gibbons

March 26, 2006

Listing the top 10 of a group is always appealing. Ten most-wanted fugitives by the FBI. Top ten songs, books, and best-dressed celebrities. And David Letterman, with his list of items such as Top Ten Reasons You Are Not Looking Forward to the NBA Playoffs. So why not list the top ten environmental problems facing America and the world?

I asked two dozen ecology graduate students what their list would be. If anyone knows what the real threats are, these people will: their opinions are science-based, not emotional. Using the Letterman approach of reading the list from 10 to 1, I present the top ten environmental problems in order of increasing importance. The total number of major problems identified by the people I asked ended up to be more than 10. Not surprisingly, some of the perceived problems are similar and interconnect, so I consolidated the students' lists to end up with the magic number 10.

10. Invasive plants and animals. The problems resulting from fire ants, Burmese pythons in the Everglades, and many more regional environmental problems have a human origin related to the introduction of exotic species.

9. Global climate change. Although "global warming" receives a lot of press, University of Georgia graduate student Brian Todd pointed out that "the global climate for the past 4 billion years has been one marked by change and relative instability. The problem we face today is the crippled ability of many ecosystems to appropriately respond to climate change as they have for the past 65 million years because we have already compromised the environment in other ways."

8. Pollution of marine habitats. The oceans are huge, but overharvesting and the degradation of marine environments are proceeding at a steady rate around the world, including a commercially extinct codfish industry and disappearing coral reefs along our own coasts.

7. Air pollution. Uncontrolled releases by industry and the excessive use of fossil fuels have led to acid rain, dissolution of the ozone layer, smog, and the general elimination of "clean air."

6. Unsustainable agriculture. The human world is dependent on food production, yet agricultural siltation, pesticide runoffs, and loss of natural habitats are constant threats to a healthy environment.

5. Threat of disease. Bird flu, West Nile virus, and mad cow disease are examples of how we could be affected overnight by unseen enemies, all a consequence of human overcrowding, overconsumption, and invasive species.

4. Water quality and quantity. Sewage from cities, unregulated releases from industrial and agricultural sites, and dumping of wastes in the oceans collectively exacerbate the worldwide problem of water pollution. Overuse of groundwater in many coastal regions leading to saltwater intrusion is a looming specter. Water wars are now a reality in the western states and even in the wetter Southeast, as evidenced in the court cases involving Alabama, Georgia, and Florida.

3. Habitat loss, fragmentation, and degradation. The loss of natural habitats because of human development and deforestation is viewed by most as the major cause of the decline in biodiversity nationally and globally. Many species are on an inexorable path toward extinction because their native habitats are gone or despoiled.

2. Human overpopulation. Most of the students ranked unchecked human population growth, which leads to overconsumption and associated world poverty, as their top culprit of environmental problems. Virtually every problem from 3 through 10 can be traced back to our simply having too many people for the resources available. Until political and religious leaders have the courage to realistically address the issue of birth control on a global scale, most of our environmental problems will worsen before they get better.

1. Apathy. Dean Croshaw, a graduate student from the University of New Orleans, offered what I rank as the number one environmental problem. A clear indicator of our foremost problem is that world leaders seldom acknowledge, let alone propose solutions to, environmental problems. For those leaders around the world chosen by a democratic election process, that apathy is condoned and mimicked by the people who elect them.

A major difference between David Letterman’s lists and mine is that none of mine are funny.

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