SAVING TROPICAL RAINFORESTS
Simply banning the timber trade or establishing reserves will not be enough to salvage the world's remaining tropical
rainforests. In order for the forests to be preserved, the underlying social, economic, and political reasons for
deforestation must be recognized and addressed. Once the issues are brought into the light, the decision can be
made about what should be done. If it is decided that rainforests must be saved, then the creation of multi-use reserves
that promote sustainable development and education of local peoples would be a good place to start. Currently about
6 percent of the world's remaining forests are protected, meaning that over 90 percent are still open for the taking. However, even this 6 percent is not safe if the proper steps towards sustainable development are not taken. Where possible, reforestation and restoration projects should be encouraged if we, humanity, hope to emerge from the current environmental situation without serious, long-term consequences.
By the year 2050 the population of Earth will likely stand between 9 and 10 billion people. The population increase in the 1990s alone dwarfed the entire population of the world in 1600. Though live births per woman have dropped significantly
in the past 50 years, the sheer number of children now in pre-reproductive age guarantees a substantial increase
in population for the next two generations regardless of the birth rate.
This tremendous population increase logically leads to the question of how many people can Earth sustain indefinitely? The exact number is unknown; estimates range from 2-16 billion. With the limited resources (water, soil, clean air) of the planet, the number depends on the quality of life future generations are willing to accept.
With current levels of consumption and waste, it may not be possible for generations of the future to attain the
lifestyle of Americans today. As a nation, Americans consume more than any society in history. For the people of
developing countries to attain the American standard of living we would need the equivalent of another three planet
Earths to accommodate their needs.
The signs that overpopulation is negatively impacting the world's living environment are everywhere. Agricultural
production reached record levels in 1998, but per capita production has been falling since 1985. All of the ocean
fisheries of the world are exploited beyond their capacity and the annual world fish catch has leveled off after growing
five-fold from 1950 to 1990. Ground-water supplies are drying up: Bangkok is pumping so much water out of the ground
that the city of seven million is sinking 14 times faster than Venice. Above ground, humanity is appropriating more than
50 percent of accessible water runoff, while we are using 40 percent of the world's net primary production. Worldwide erosion
of precious topsoil is seriously impacting agriculture and causing more than $6 billion in damage to hydroelectric
installations and irrigation systems every year. More people live in dire poverty than ever before despite gains
in the standard of living among those in wealthy countries and some in developing countries. Global climate change
threatens to drastically alter weather and rainfall patterns and cause a rise in sea level that could engulf island
Many argue there is a technological fix for every problem facing humanity: to improve agriculture, use genetic
engineering to boost crop yields and enable crops to grow on increasingly marginal land; to end world hunger, convert
nitrogenased petroleum to food and improve freshwater aquaculture; to solve water woes, tow icebergs from the
poles to coastal cities; to save biodiversity, create genetic libraries of species as they disappear; to eliminate
Cold War radioactive sludge, engineer waste-eating bacteria; to solve fuel problems, generate endless supplies of clean energy with cold fusion; to solve climate change, engineer the atmosphere and oceans. Governments, venture capitalists, and stock markets will fund these endeavors to support or profit from the effort to starve off environmental and social calamity, proponents say.
Even if these hopeful long-shot schemes are successful, they will be incredibly expensive to implement and maintain.
Take the simple case of fuelwood: the UN estimates that the cost of establishing fuelwood plantations to replace
harvesting from natural forests is $12 billion per year. The cost of replacing watershed forests, which insure
the flow of clean, fresh water to cities, with desalination plants would be in the hundreds of millions to billions
of dollars for each large city. The cost of maintaining the forests as intact ecosystems to provide this service,
in additions to others, is less than one-tenth of this cost.
There was an attempt to create a replica of Earth systems with the construction of Biosphere II in early 1990 in
the desert of Arizona. This $200 million project was an elaborate experiment to see if man could recreate a miniature
Earth using technology based on our best understanding of biological systems. The 3.15-acre (1.25-ha) enclosure was stocked
with soil, air, water, and fragments of various ecosystems (coral reef, desert, wetland, savanna, pond, scrubland,
ocean, and rainforest) including natural flora and fauna. On Sept. 26, 1991, eight scientists sealed themselves
into the compound for a two-year stay. Within five months the atmospheric oxygen content of Biosphere II dropped
from 21 percent to 14 percent, while carbon-dioxide and nitrous-oxide levels rose dangerously despite a sophisticated recycling
system. Oxygen had to be pumped in to sustain Biosphere II. The scientists managed to stay in Biosphere II the
full two years; however the other residents were not so lucky. By the time the seal was broken, 19 of 25 vertebrate
species were extinct along with all the pollinators. The populations of "weedier" species like vines,
cockroaches, and ants had exploded. Despite the failure of the project to sustain the scientists independently
of Earth, an important lesson was learned; man has a long way to go before we are able to recreate viable ecosystems.
The evidence suggests we are rapidly approaching a severe environmental and population bottleneck. It is time to
consider whether we want to bet on safe passage through this bottleneck despite the ruinously high stakes for humanity
and the life we prefer. In the past, magnificent civilizations—the Egyptians, Romans, Easter Islanders, Mayans—have fallen as their populations exceeded the biological carrying capacity of their local environments. Maybe
this time around it will be different because of our superior technology. Besides we learn from our mistakes, right?
E.O. Wilson asks if it is worth the wager. He argues that it is best to err on the side of caution; a false positive diagnosis
is an inconvenience, but a false negative diagnosis can be catastrophic. Imagine a person who receives a false
negative on an AIDS test. The person could spread the virus to numerous others, falsely believing he or she was
uninfected. By allowing environmental destruction and rampant population growth to continue, humanity is "effectively
saying we are totally certain that future generations can manage without many if not most of the [environmental]
benefits we enjoy today."
Saving the forests, oceans, wetlands, deserts, and tundra of the world may require a fundamental change in the
way we humans see the world around us. It is our underlying philosophy, one that has been conditioned since birth,
that has turned so many of Earth's unique ecosystems into places in peril today.
As much as we may want to believe it, man is not apart from nature. We are not exempt from the laws of nature nor
the sole heir of all the precious resources of this planet. Our place in the universe is not to conquer Earth and
cultivate the entire planet to suit our needs, while extinguishing those species that do not directly benefit us.
It is not important whether you consider man divinely inspired, or a small cog in the Gaia
(Mother Earth) system, or merely a territorial primate species that evolved to
the point where it could develop technology to dominate all other species. What is imperative
to our species and all other species is biological diversity. This biodiversity crisis that we are facing today
transcends religions, though traditional religions, both tribal and institutional, lend support to the preservation
What makes life on Earth livable for our species is biodiversity—from tigers in Bhutan to gila monsters in the United States to horned beetles in Africa to the goldfish in your home to tube worms in hydrothermal vents in the deep ocean to
sea cucumbers living on the coral reefs of Madagascar to the mites on your cheese. By extinguishing hotbeds of biodiversity—rainforests, wetlands, coral reefs, and grasslands—we are destroying a part of ourselves. Biodiversity will recover after humanity is gone, but in the meantime,
the continuing loss of our fellow species will make Earth an awfully crowded, but lonely, place.
Past extinctions have shown it takes at least 5 million years to restore biodiversity to the level equal to that
before the extinction event event. Our actions today will determine whether Earth will be biologically impoverished
for the 500 trillion or more humans that will inhabit the Earth during that future period.
The extinction event that is occurring as you read these words rivals the extinctions caused by natural disasters
of global ice ages, planetary collisions, atmospheric poisoning, and variations in solar radiation. The difference
is that this extinction was conceived by humans and subject to human decisions. We are the last, best hope for
life as we prefer it on this planet.
[AUTHOR'S NOTE: Parts of this conclusion draws from E.O. Wilson's Consilience
—Random House 1999]
Rainforest in West Papua, Indonesian New Guinea. (Photo by R. Butler)
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Continued / Next: Rainforest index
Selection of information sources
The conclusion draws heavily on ideas and examples found in the last section of Edward O. Wilson's Consilience: The Unity of Knowledge (New York: Alfred A. Knopf, 1998). He discusses population growth and concludes the number of people Earth can sustain depends on the quality of life future generations are willing to accept. J.E. Cohen (How Many People Can the Earth Support? New York: W.W. Norton: 1995 and P.R. Ehrlich and J.P. Holden "Impact of population growth" Science 171: 1212-1217, 1971 go into greater detail on Earth's human carrying capacity. Norman Myers ("The world's forests and their ecosystem services," in Nature's Services - Societal Dependence on Natural Ecosystems, ed G.C. Daily, Washington D.C.: Island Press, 1997) calculates that for people of developing countries to attain the standard of living enjoyed by Americans we would need the equivalent of another three planet Earths.
Myers (1997) and Wilson (1998) review some of the signs that human population is negatively impacting the world environment such as agricultural per capita production, ocean fisheries, ground water supplies, erosion, poverty, and climate change. Vitousek, P.M. et al. ("Human appropriation of the products of photosynthesis," BioScience Vol. 36, 368-373, 1986) estimate that humans are are appropriating 40% of net primary production.
J.E. Lovelock presented his Gaia theory in Gaia: A New Look at Life on Earth, Oxford: Oxford University Press, 1982.
Technological fixes fot the world's environmental problems are mention in Wilson's consilience and discusses at greater length in J.H. Ausubel, "Can technology spare the earth?" American Scientist 84:166-178 1996. Natural plastic - a plastic made from plants rather than petroleum - is announced in Warren, S. "Cargill, Dow Chemical Join To Make 'Natural Plastic,'" The Wall Street Journal, 1/11/00.
The UN estimate for the cost of establishing fuelwood plantations to replace harvesting from natural forests is provided by Myers, Norman "The world's forests: problems and potentials," Environmental Conservation 23 (2):158-168, 1996.
Wilson (1998) provides a succinct review of the Biosphere II project, while J.E. Cohen and D. Tilman "Biosphere 2 and Biodiversity: the Lessons Learned So Far," Science 274:1150-1151, 1996 provide a more academic look at this elaborate experiment to recreate miniature ecosystems.
The role of environmental degradation and overpopulation in the downfall of great civilizations of antiquity is discussed in C. Runnels, "Environmental degradation in ancient Greece," Scientific American 272 (3): 72-75, 1995 [Greece]; R. Adams, Heartland of Cities, Chicago: University of Chicago Press, 1981 [Mesopotamia]; Sharer, R.J., The Ancient Maya, Stanford: Stanford University Press, 1994 [Mayans]; and Diamond, J., "Easter's End," Discover. Vol. 16, No. 8, Aug 1995 [Easter Island]].
The loneliness of a biologically impoverished Earth is a subject explored by David Quammen in Wild Thoughts from Wild Places, New York: Scribner 1998 and E.O. Wilson in On human nature, Cambridge: Harvard University Press, 1978
Myers, N. ("The world's forests and their ecosystem services," in Nature's Services - Societal Dependence on Natural Ecosystems, Ed G.C. Daily, Washington D.C.: Island Press, 1997) notes that the actions we take today will determine whether Earth will be biologically impoverished for the 500 trillion or more humans that may inhabit the earth in the future.