Myth: We shouldn't worry; the environment will heal itself.

Fact: The environment heals slowly -- we are destroying it rapidly.


The environment will heal itself, all right, but humans should worry how. The population explosion is causing damage at a faster rate than the earth's ability to recover, and the damage threatens to become permanent. Furthermore, when an expanding population meets shrinking resources, the results are starvation, poorer health and pitched competition for survival. Among other resources, the world has reached its limit in crop harvests, and is declining in animal species, rain forests, top soil, fish stocks, and fresh water.


There are two types of damage that humans cause to the environment. One is long-term, even permanent destruction, such as the extinction of a species or the radioactive poisoning of Chernobyl.

The second is short-term damage -- and this is where conservatives latch onto false hope. It is true that the environment has the capacity to heal itself in some ways. Endangered species can rebound, the earth can create its own ozone, the oceans can absorb greenhouse gases. The rate of recovery depends on the type of damage being done. Species can recover in a few decades; ozone, a century; old growth forests, several centuries; the cooling of radioactive waste, hundreds of thousands of years. But here is a critical point: the environment cannot recover while we are still increasing the damage to it. In many areas, humans are destroying the environment faster than it can recover, as the following statistics will show. And if we continue in our current ways, the damage will inevitably become permanent.

In surveying statistics on the environment, it is important to keep two opposing trends in mind. One is the population explosion:

World population growth (1)

                 Year      Length of
Population       reached   Interval
1 billion         1804      200,000 years after rise of modern humans
2 billion         1927          123 years
3 billion         1960           33
4 billion         1974           14
5 billion         1987           13
6 billion est.    1998           11
7 billion est.    2009           11
8 billion est.    2021           12
9 billion est.    2035           14
10 billion est.   2054           19
11 billion est.   2093           39

At present, we are adding the population of China to this planet every decade. Feeding and supplying this population explosion are placing huge demands on the environment. And this brings us to the other, opposing trend: the environment's resources are either reaching their limit or shrinking. The result will be like two trains barreling towards each other on the same railroad track. Biologists, historians and economists all concur that whenever growing populations have met shrinking resources, the results have been pitched competition for survival. This is why the above chart sees population growth slowing over the next century.

The population explosion is compelling a growing number of scientists to advocate replacing our growth economy with a sustained economy. Lester Brown, President of Worldwatch Institute, writes:

In the long run, humans will have no choice in establishing a sustained economy. Either we establish it ourselves, or nature will do it for us - and we can be sure that nature will not be as kind to ourselves as we are.

With this in mind, we should review the statistics showing which wildlife and natural resources have either reached their limit or are shrinking. In both cases, it is an expanding human population that pays the price, in the form of starvation, poorer health and increased competition:

The first statistic is that 100 species a day are going extinct due to human causes alone. This is a sharp increase from a mere two centuries ago, when this rate was almost at zero. If this extinction rate continues to match the rising human population rate, then in 50 years the earth will have suffered the second worst mass extinction in history, after the dinosaurs. (3)

A few scientists question how well we can know what is happening to the world's 4 million-plus species. Fortunately, scientists can get an excellent idea from the study of birds. Birds are nearly perfect barometers of the biosystem's health for several reasons: we have already identified all 9,600-plus species of birds; birds are easy to track and record; they occur all over the world; and they respond quickly to changes in the environment. Therefore, they are ideal studies on the environment. Unfortunately, the state of the world's bird population shows it to be in deep trouble. Some 70 percent of all bird species are either in decline or facing extinction. (4) This is serious not only for the larger devastation it represents, but also because birds make vital contributions to the life cycle. Birds pollinate flowers and trees, spread seeds through their droppings, and keep the rodent population in check. The decline of birds will have profound repercussions in the ecosystem.

The second statistic is radioactive waste. Once produced, these nuclear wastes have lethal half-lives so long that disaster is absolutely guaranteed by the laws of chance. As of 1992, the United States alone has produced over 25,000 metric tons of nuclear waste. (5) Much of it is put into supposedly "safe" barrels, taken off shore and dumped into the ocean. Keep in mind that humans have no known material that will last thousands of years, especially under high heat. Concrete crumbles in less than a hundred years; plastic melts under the high temperatures of radioactivity. Also keep in mind that the ocean is a biologically and chemically rich and active environment, and nature has an astounding capacity to absorb and recycle anything within it. If we can adapt organisms to eat oil, Agent Orange and DDT, it is difficult to imagine these barrels will be safe from natural attack for long.

The third statistic is the rain forests of Brazil. Humans are burning them at record rates. We've all heard the statistic that every 10 seconds, a section of forest the size of a football field goes up in flames. The rain forests cover only 2 percent of the earth's surface, but they produce half of our oxygen, as well as recycle a small portion of our greenhouse gases. Destroying them is a profoundly stupid idea. They also are home to half the world's species - a rich abundance of life and diversity that has allowed scientists to isolate medicines and cures for diseases. So far, humans have burned 10% of the forests and killed or affected the habitats and migration patterns of 30% of the area's life.

The fourth statistic is that we are threatening to fish out the oceans. Soaring demand between 1950 and 1989 drove the world annual fish catch from 22 to 100 million tons. But something unusual occurred over the next five years. Despite growing demand, the fish catch hit its limit, even declining slightly. A search for the reason why reveals that all 17 major fishing areas of the world have either reached or exceeded their natural limits, and nine are in serious decline. (6) Industry horror stories began as early as the 1970s, when Iceland's fishing industry was decimated and the Peruvian anchovy catch fell from 12 million to 2 million tons in just three years. In 1993, some 50,000 Canadian fishers had lost their jobs due to disappearing cod in the North Atlantic. (7) With 200 million people around the world employed in fishing, you can imagine the tremendous political pressure to keep fishing rates at their current level. (8)

The fifth statistic is grain. What happened with fish is also occurring in grain production. From 1950 to 1984, world grain production rose from 631 million tons to 1.649 billion tons. (9) Much of this increase occurred for two reasons: farmers expanded their farmland, and dramatically boosted their yield per acre through the use of fertilizers. In 1984, however, world grain production reached its natural limits. Despite soaring demand, average yearly production has remained stuck at 1984 levels. The first reason is that new farmland is becoming more and more difficult to find. The second is that the mass introduction of fertilizer is now complete, and we have seen all the improvements that fertilization can bring; unfortunately, adding even more fertilizer does not increase yield.

Despite a growing population, providers have been unable to supply either more grain or fish. This has resulted in less food for the average person. Grain production per person has fallen from 346 to 303 kilograms from 1984 to 1993. (10) Fish catch per person has fallen from 19.2 to 17.6 kilograms from 1989 to 1993. (11) These levels are not satisfactory; experts calculate that the 1992 grain yield was nutritionally inadequate for 1 billion people. (12) Vegetarians point out that people can make more efficient use of their grain (and probably live healthier lives) by consuming less meat. For example, it takes two pounds of grain to produce a pound of poultry; four pounds of grain for a pound of pork, and seven pounds of grain for a pound of beef. (13)

The sixth statistic is the gradual loss of our farmland. There are two causes for this. One is that poor farming techniques allow rain to erode topsoil faster than usual. In his book Earth in the Balance, Al Gore writes that "the Mississippi River carries away millions of tons of topsoil from farms in the middle of America" and that Iowa, which "used to have an average of sixteen inches of the best topsoil in the world... now is down to eight inches." Rush Limbaugh correctly points out that, "thanks to technological breakthroughs, fewer and fewer acres have been suffering severe erosion in the United States." (14) But this is not to imply, as Rush does, that slower erosion rates are still not a serious problem. After all, it still represents a shrinking resource in the face of a growing population. And we know that once farmland turns into desert, there is no hope of reviving it. Thousands of years ago, the once famous "Fertile Crescent" supported a major population in the Middle East, but it was farmed so much, and so poorly, that it turned into a desert.

But it doesn't take the loss of topsoil to reduce grain production; ruining the soil accomplishes the same thing. Today, a growing percentage of farmland is being salt-poisoned. This occurs when water is irrigated into the land, bringing with it all its minerals; when the water evaporates, salt concentrations are left behind. As the concentrations grow, the land produces less and less, and finally becomes ruined. Treating this problem is enormously expensive. Experts estimate that 8 to 12 percent of the world's irrigated land suffers from serious salinization, and another 25 to 33 percent suffer from moderate salinization. (15)

The seventh statistic is fresh water. The continental water basins of farming nations around the world are dropping, as demand for water grows faster than the rain cycle can replenish it. (16) As a short-term solution to fulfilling the population's immediate water needs, nations are diverting water from agriculture to cities. Unfortunately, lack of water for irrigation also lowers grain production, so this is really no solution at all. Attempts to deal with the problem have led to the creation of an active water market in the western United States. In 1992, 14 western states conducted 146 water transactions, with most of the water going from agriculture to cities. (17) Obviously, the depletion of our groundwater is not a sustainable activity.

And these examples are not to mention the deadliest threats to human survival: global warming and the destruction of the ozone layer. Global warming is dangerous because it would cause more severe weather, increase the range of deserts, melt the polar ice caps, cause a rise in sea level (which, according to the fossil record, is a major cause of mass extinctions), as well as expand the habitat of deadly tropical diseases. The destruction of the ozone layer is dangerous because this layer protects all life from the sun's deadly ultraviolet rays. Thanks to quick action in international diplomacy, the man-made chemicals responsible for the destruction of the ozone layer have already been banned. But there is no such luck banning fossil fuels. The oil companies seem to be politically omnipotent.

On the other hand, one could look at it this way. The environment will heal itself -- but not in the way humans would like it to.

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1. Population Division, Department for Economic and Social Information and Policy Analysis, World Population Growth from Year 0 to Stabilization, (United Nations, New York), mimeograph, 6/7/94.

2. Lester Brown, Vital Signs 1994, (New York: W.W. Norton & Company, Inc., 1994), p. 15.

3. Jon Erickson, The Living Earth, (Blue Ridge Summit: TAB Books, Inc., 1989), p. 169.

4. Worldwatch estimates based on Nigel Collar, BirdLife International, Cambridge, U.K., as cited by Vital Signs 1994, p. 128.

5. Nuclear Assurance Corporation, Atlanta, GA. Cited by The American Almanac, table 953.

6. U.N. Food and Agricultural Organization, Yearbook of Fishery Statistics: Catches and Landings (Rome: various years), as cited by Vital Signs 1994, pp. 32-3.

7. Mark Clayton, "Hunt for Jobs Intensifies as Fishing Industry Implodes," Christian Science Monitor, August 25, 1993.

8. Lennox Hinds, "World Marine Fisheries," Marine Policy, September 1992.

9. USDA, World Grain Database (Washington D.C., 1992); USDA, World Grain Situation and Outlook, Washington D.C., November 1993.

10. Ibid.

11. U.N. FAO, Yearbook of Fishery Statistics: Catchings and Landings (Rome: various years); 1992-3 data from Maurizio Perotti; population data from U.S. Bureau of Census.

12. Brown, p. 26.

13. Conversion ratio for grain to beef based on Allen Baker, Feed Situation and Outlook staff, Economic Research Service [ERS], USDA, Washington, D.C., private communication with Lester Brown, April 27, 1992; pork data from Leland Southard, Livestock and Poultry Situation and Outlook staff, ERS, USDA, Washington, D.C., private communication with Lester Brown, April 27, 1992; poultry ratio derived from data in Richard V. Bishop et al., The World Poultry Market - Government Intervention and Multilateral Policy Reform (Washington, D.C., USDA, 1990).

14. Rush Limbaugh, See, I Told You So (New York: Simon & Schuster, 1994), p. 180.

15. Dina Umali, Irrigation-Induced Salinity: A Growing Problem for Development and Environment (Washington, D.C., World Bank, 1993).

16. Sandra Postel, Last Oasis: Facing Water Scarcity (New York: W.W. Norton & Company, 1992).

17. "1992 Annual Transactions Review: Drought Stimulates Contractual Innovation," Water Strategist, January 1993.