[Paleopsych] NYT: How Much Is Nature Worth? For You, $33 Trillion

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How Much Is Nature Worth? For You, $33 Trillion
The New York Times, 97.5.20
[Note the date. I found this when doing some Spring cleaning. No, 
I won't say which spring!]

By WILLIAM K. STEVENS

   HOW much is nature worth?

   Some say the question is unanswerable, that it is impossible to 
calculate a dollar value for the natural world. Others say the question 
should not even be asked; that nature, like human life, is priceless and 
should not be devalued as if it were a mere commodity.

    But economists and ecologists are searching for the answer anyway. 
Nature performs valuable, practical, measurable functions, they say; 
without them the human economy could not exist, and in many cases people 
could not duplicate them as cheaply -- or at all. And they say it is time 
that the value of these functions is considered when economic decisions 
are made.

   One notable example of nature's economic value that they cite is the 
purification of New York City's water supply by microorganisms as the 
water percolates through the soil of the Catskills. The city plans to 
spend $660 million to preserve that watershed in good health; the 
alternative, a water treatment plant, would have cost $4 billion to build.

   Nature performs a long list of other economic services as well. Flood 
control, soil formation, pollination, food and timber production, 
provision of the raw material for new medicines, recreational 
opportunities and the maintenance of a favorable climate are among them.

   But like a well that is taken for granted until it runs dry, these 
ecosystem services, as ecologists call them, have long been overlooked 
until they either no longer work or are gone -- as, for instance, when the 
widespread destruction of Midwestern wetlands meant they could no longer 
perform their natural function of sponging up water from disastrous floods 
like those of recent years.

   And to the extent ecosystem services are noticed at all, people have 
tended to regard them as free.

   Now, as human activity gradually uses up or destroys this natural 
capital and eats away at the natural systems that provide many of the 
services, many experts are insisting that the worth of ecosystem services 
must be calculated and heeded.

   The results of the latest and in some ways the most ambitious effort to 
place a dollar value on natural capital and services were announced last 
week.

   Thirteen ecologists, economists and geographers, in a report in the 
journal Nature, estimated the present global value of 17 ecosystem 
services at $16 trillion to $54 trillion a year, with a likely figure of 
at least $33 trillion. Most of this, they said, lies outside formal 
markets and is therefore not reflected in market prices, the customary 
gauge of economic value. Their estimate, they said, compares with $18 
trillion for the gross national product of the world, which is all the 
goods and services produced by people each year.

   The researchers, who based their conclusion on other published studies 
and their own calculations, freely point out that their estimate is a 
rough approximation, a first step that is mainly intended to determine 
whether ecosystem services amount to "big potatoes or small potatoes," in 
the words of Dr. Robert Costanza, an ecological economist at the 
University of Maryland who headed the study. "We come away from this 
thinking this is a minimum estimate," Dr. Costanza said.

   Virtually everyone agrees that without the natural world, the human 
economy and indeed human life could not exist. In this sense, the value of 
nature is infinite, immeasurable. To some conservationists, this is all 
that needs to be said. "Common sense and what little we have left of the 
wisdom of our ancestors tells us that if we ruin the earth, we will suffer 
grievously," said Dr. David Ehrenfeld, a conservation biologist at Rutgers 
University. He said he accepted the results of the Costanza study, which 
he regards as conservative, but added: "I am afraid that I don't see much 
hope for a civilization so stupid that it demands a quantitative estimate 
of the value of its own umbilical cord."

   Dr. Ehrenfeld and some other conservationists believe that moral 
arguments for saving nature are more persuasive than economic ones. But in 
the view of Dr. Costanza and others, moral and economic arguments should 
be pursued in parallel.

   People make economic choices involving nature all the time, according 
to this view, but they do so without taking all the costs into account. 
For example, the dollar value of a wetland's flood-protection and water 
cleansing abilities has not traditionally been considered when it is lost 
to a shopping center. The result is a creeping depletion of natural 
wealth.

   If such costs were reflected in day-to-day transactions, these 
theorists say, society would pay more attention to what is lost when land 
is "developed."

   "We can't wait until we've disrupted the planet's life-support system 
beyond repair," said Dr. Gretchen C. Daily, a conservation biologist at 
Stanford University. She is the editor of a recent collection of papers on 
the subject, "Nature's Services; Societal Dependence on Natural 
Ecosystems," published as a book by Island Press. Once gone, she noted, 
many of these ecological assets would be difficult, if not impossible, to 
replace; it can take thousands of years to recharge depleted aquifers or 
replenish topsoil.

   Until now, fledgling efforts at what is called "green accounting" have 
been pursued largely at the national level. In a widely applauded attempt 
of this kind, Dr. Robert Repetto, senior economist at the World Resources 
Institute, a Washington-based research organization, has analyzed the 
economies of Indonesia and Costa Rica. In Indonesia, he and colleagues 
calculated that losses from soil erosion reduced the net value of crops by 
about 40 percent and that the loss of value from deforestation was four 
times as high as the value of the timber extracted. They also concluded 
that depletion of Costa Rica's soils, forests and fisheries resulted in a 
25 percent to 30 percent reduction in potential economic growth.

   A nascent effort to introduce a measure of natural-resource accounting 
into the United States' official calculation of economic worth was made in 
1993, but it is on hold pending a Congressionally ordered study of the 
soundness of the approach by the National Academy of Sciences. A report is 
due this year.

   The new Costanza study is not really an exercise in green accounting, 
and some experts question its practical usefulness while others express 
skepticism about its basic finding.

   "There's no way of knowing how good this number is," Dr. Repetto said 
of the study's estimate of $33 trillion for the global value of ecosystem 
services. "They've made some heroic assumptions. I suppose it's useful for 
rhetorical purposes." But the number, he said, is less important than the 
fundamental point made by the study "that ecosystem services are 
important; I don't think reasonable people would deny that."

   Other experts see more utility in the analysis. The study has succeeded 
in providing "a conservative estimate of what the environment does for 
us," said Dr. Stuart Pimm, an ecologist at the University of Tennessee who 
wrote a commentary on the Costanza study in Nature. "So often," he said, 
"people concerned with protecting the environment go up against these very 
highly detailed economic analyses and feel they don't have anything in 
kind with which to respond." In the tables of specific ecosystem services 
that accompany the study, he said, "what Costanza et al. has done is 
provide a checklist" that national and local policy makers can use in 
attempting to make a rough gauge of the economic worth of their natural 
assets.

   One table, for instance, lists specific ecosystem services, and their 
supposed value, for 11 biomes, or types of natural areas. These include 
the open ocean, estuaries, seagrass and algae beds, coral reefs, 
continental shelves, tropical forests, temperate forests, grasslands and 
rangelands, tidal marshes and mangroves, wetlands and flood plains and 
lakes and rivers.

   The next step, Dr. Costanza says, is to delineate more clearly the 
explicit linkages between particular local ecosystems and local economies. 
For example, how much of the value of the Louisiana shrimp catch is 
attributable to the wetlands in which the shrimp reproduce and grow? But 
since wetlands perform other services as well, the wetlands' value as a 
shrimp nursery would be only a minimum indication of their overall value.

   The same applies, for example, to the Catskill watershed, which serves 
other economic functions besides providing and cleaning New York City's 
water -- attracting tourists, for instance. "Nobody thinks the Catskills 
are worth only $4 billion," Dr. Daily said, referring to the cost of 
replacing the Catskills' water-cleansing function.

   Assuming the value of ecosystem services could eventually be 
established, how might economic policies be changed? For openers, Dr. 
Daily and others say, government subsidies that distort the value of 
natural resources -- in fisheries and logging, for example -- should be 
abolished. Also, tax incentives might be given to landowners to protect 
the long-term assets represented by natural capital rather than using them 
for short-term gain.

   Some experts advocate applying traditional economic arrangements to 
ecosystem services. For instance, Dr. Graciela Chichilnisky and Dr. 
Geoffrey Heal, economists at Columbia University, have proposed selling 
investment shares in a given ecosystem. Using the Catskill watershed as an 
illustration, they say that the capital thus raised would pay for 
preserving the watershed. Returns to investors would come either from a 
share of the costs saved by not having to build a treatment plant or, if 
the investment were private, by actually selling ecosystem services. In 
the case of a watershed, clean water would be sold.

   But, says Dr. Daily, "the first thing is getting the prices right."


   GRAPHIC: Chart: "The Value of the Natural World"

A new attempt by 13 scientists to assign dollar vlues to essential 
services performed for the human economy by the natural world divides the 
services into the following 17 Categories.

Gas Regulation
Carbon dioxide/oxygen balance, ozone for ultraviolet protection

Climate Regulation
Greenhouse gas regulation

Disturbance Regulation
Storm protection, flood control, drought recovery

Water Regulation
Provision of water for irrigation, mills or transportation

Water Supply
Provision of water by watersheds, reservoirs and aquifers

Erosion control and sediment Retention
Prevention of soil loss by wind, runoff, etc; storage of silt in lakes and
wetlands

Soil Formation
Weathering of rock and accumulation of organic material

Nutrient Cycling
Nitrogen fixation

Waste Treatment
Pollution control, detoxification

Pollination
Pollinators for plant reproduction

Biological Control
Predator control of prey species

Refuges
Nurseries, habitat for migratory species

Food Production
Production of fish, game, crops, nuts and fruits by hunting, fishing, gathering
of subsistence farming

Raw Materials
Production of lumber, fuel or fodder

Genetic Resources
Medicines, Resistance genes for crops, ornamental plant species, pets

Recreation
Ecotourism, sports fishing, other outdoor recreation

Cultural
Esthetic, artistic, educational, spiritual and/or scientific values of
ecosystems

(Source: Nature)