ivanthomson-ga,
Wild places are worth $33.3 trillion dollars.
At least, that's the answer given in a seminal and widely-read paper
on the topic of valuing the world's natural places:
"The Value of the World's Ecosystem Services and Natural Capital"
R. Costanza et al
Nature Vol. 387 (1997)
Thanks to the graciousness of the authors, and of Nature magazine, the
complete article is available online, and at no charge, at:
http://www.esd.ornl.gov/benefits_conference/nature_paper.pdf
The key dollar figures are summarized here:
http://pubs.wri.org/pubs_content_text.cfm?ContentID=1387
Valuing ecosystem services
===========================================
Ecosystem services.................... Value
.................................(trillion $US)
Soil formation .........................17.1
Recreation ..............................3.0
Nutrient cycling ........................2.3
Water regulation and supply .............2.3
Climate regulation
(temperature and precipitation)..........1.8
Habitat .................................1.4
Flood and storm protection ..............1.1
Food and raw materials production....... 0.8
Genetic resources .......................0.8
Atmospheric gas balance................. 0.7
Pollination .............................0.4
All other services...................... 1.6
Total value of ecosystem services...... 33.3
=============================================
This figure is larger than the size of the total world economy in 1997!
A more recent and very comprehensive discussion of valuing the earth's
wild and natural places can be found in this 2004 study from the
National Academy of Sciences:
http://newton.nap.edu/books/030909318X/html
Valuing Ecosystem Services: Toward Better Environmental Decision-Making
Unlike the Costanza paper (am I the only one who thinks of Seinfeld?),
the National Academy book doesn't fix a particular value on the
earth's ecosystems, but instead discusses the many factors involved in
trying to conduct such an exercise.
The NAS report includes an in-depth, and fairly critical, discussion
of the Constanza paper on page 188:
http://www.nap.edu/openbook/030909318X/html/188.html
Although the links above are based on only two sources of information,
I believe you will find that these are the most comprehensive and
well-regarded resources available on this intriguing topic. The
figure of $33+ trillion as the value of the world's natural heritage
is probably the most widely-cited figure available as an answer to
this question:
://www.google.com/search?sourceid=navclient&ie=UTF-8&rls=GGLD,GGLD:2003-43,GGLD:en&q=%2233%2e%2e34+trillion%22+costanza
I trust this information fully answers your question.
However, please don't rate this answer until you have everything you
need. If you would like any additional information, just post a
Request for Clarification to let me know how I can assist you further,
and I'm at your service.
All the best,
pafalafa-ga |